You might choose to use the compact numeric keys like 0 & 1 instead!  

P.S.: At the following thread, you can see 3 different styles to check for key input:

http://forum.processing.org/topic/trying-to-display-a-character-on-top-of-my-maze

Leave them as simple as possible. Focus only on storing the state of each key!

Choose 1 outta the 3 methods shown at the link above as your solution.  

If the player is holding down the d key to walk and they press the punch key, how can i interrupt the d key so that the punch animation takes place and resume the d key and moving after wards?

That decision should take place inside the functions responsible for that type of animation.

You shouldn't clear the state that keyCode 'D' is being pressed.

Rather, take the decision of not walking left while "punch" keyCode is active!

In short -> Do not walk while punching! No matter is the player is trying to! 

It is often a good idea to re-post your current code if you had modified it enough and have more doubts!  

***EDIT**** i fixed it by adding to one of the if statements to check if a boolean was false and made the movement speed 0 while the animation ran and reset it after the animation was done

3. if ( (d== true || a == true) && (w==false && s==false&&cntrl==false&&drpdwn==false)) {
4.       if (frameCount % 4 == 0) frame++;
5.       if (frame >= 5) frame = 0;
6.     } 
7. 
   
8. 
   
9. if (drpdwn == true&&s==false&&w==false) {
10.       if ( punch == false) {
11.         frame=22;
12.         punch = true;
13.       }
14.       speedp1=0;
15.       if (frameCount % 4 == 0) frame++;
16.       if (frame>=30) {
17.         speedp1=3;
18.         punch = false;
19.         drpdwn = false;
20.       }
21.     }

as im sure youve guessed im fairly new to processing, and i dont know the most efficent ways to do things( just what ive been taught plus a little research ive done) I thought i had it so that it would interupt, but instead it waits until i let go of the walking key, then plays the animation, and i think part of the reason im having this issue is that some of the code is being processed withing a class, while others are being processed in a void i created to run during draw, im almost done my game, but ive been having issues with the animations like i said. maybe you could suggest a better way for me to do it? sorry to ask so many questions. heres my code:

2. // player 1
3. 
   
4. // w,a,d move and jump
5. //s block
6. //dropdown - punch
7. // cntrl - kick
8. 
   
9. 
   
10. 
    
11. //character 1----------------
12. 
    
13. 
    
14. float movep1 = 10;
15. float jump1 = 250;
16. float jumps1 =.2;
17. float gravity1 = -5;
18. float speedp1 = 3;
19. boolean a = false;
20. boolean w = false;
21. boolean d = false;
22. boolean s = false;
23. boolean drpdwn = false;
24. boolean cntrl = false;
25. 
    
26. //---------------------------
27. //character2-----------------
28. 
    
29. 
    
30. float movep2 = 290;
31. float jump2 = 250;
32. float jumps2 =.2;
33. float gravity2 = -5;
34. float speedp2 = 3;
35. boolean up = false;
36. boolean left = false;
37. boolean down = false;
38. boolean right = false;
39. 
    
40. 
    
41. //---------------------------
42. //BACKGROUNDS----------------
43. PImage background[] = new PImage[1];
44. PImage img;
45. //SPRITES--------------------
46. //////////BILL///////////////
47. PImage bill[] = new PImage[31];
48. Player1 p1 = new Player1();
49. 
    
50. void setup() {
51.   size(1440, 900);
52.   imageMode(CENTER);
53. 
    
54.   // load backgrounds
55.   for (int b=0; b<1; b++) {
56.     String filename = "background_"+b+".png";
57.     background[b]=loadImage(filename);
58.     println("loading " + filename);
59.   }
60.   img = background[0];
61.   // load bill animation
62.   for (int i=0; i<bill.length; i++) {
63.     String filename = "bill" + i + ".png";
64.     bill[i]= loadImage(filename);
65.     println("loading " + filename);
66.   }
67. }
68. 
    
69. //STATES
70. void draw() {
71.   runGame();
72. }
73. // Main GAME
74. void runGame() {
75.   background(65);
76.   //image(background[0],0,0);
77.   p1.display();
78.   p1.move(movep1, jump1);
79.   // move main character
80.   //right
81.   if (d == true) {
82.     if (movep1 >= width) {
83.     }
84.     else {
85.       movep1 += speedp1;
86.     }
87.   }
88.   //block
89.   if (s == true) {
90.   }
91.   //left
92.   if (a == true) {
93.     if (movep1 <=0) {
94.     }
95.     else {
96.       movep1 -= speedp1;
97.     }
98.   }
99.   //jump
100.   if (w == true) {
101. 
     
102.     jump1 = jump1+gravity1;
103.     gravity1 = gravity1 + jumps1;
104.     if ( jump1 >= 250) {
105.       gravity1 = gravity1*-1;
106.       gravity1= -5;
107.       w=false;
108.     }
109.   }
110.   //move character 2
111.   //move right
112.   if (right == true) {
113.     if (movep2 >= width) {
114.     }
115.     else {
116.       movep2 += speedp2;
117.     }
118.   }
119.   //move left
120.   if (left == true) {
121.     if (movep2 <= 0) {
122.     } 
123.     else {
124.       movep2 -= speedp2;
125.     }
126.   }
127.   //jump
128.   if (up == true) {
129. 
     
130.     jump2 = jump2+gravity2;
131.     gravity2 = gravity2 + jumps2;
132.     if ( jump2 >= 250) {
133.       gravity2 = gravity2*-1;
134.       gravity2 =-5;
135.       up=false;
136.     }
137.   }
138.   ellipse(movep1, jump1, 50, 50);
139.   ellipse(movep2, jump2, 50, 50);
140. }
141. 
     
142. 
     
143. 
     
144. /// KEY MOVE CODE
145. void keyPressed() {
146.   final int k = keyCode;
147.   print (k + "\t");
148. 
     
149.   println(keyCode);
150.   if (k == 'D') {
151.     d = true;
152.   }
153.   if (k =='A') {
154.     a = true;
155.   }
156.   if (k =='W') {
157.     w = true;
158.   }
159.   if (k =='S') {
160.     s = true;
161.     a=false;
162.     d = false;
163.   }
164.   if (k == 0) { 
165.     drpdwn = true;
166.   }
167.   if (k == 17) {
168.     cntrl = true;
169.   }
170.   if (k == LEFT/*left*/) {
171.     left = true;
172.   }
173.   if (k == UP/*up*/) {
174.     up = true;
175.   }
176. 
     
177.   if (k== RIGHT/*right*/) {
178.     right = true;
179.   }
180.   if (k== DOWN) {
181.     down = true;
182.   }
183. }
184. 
     
185. void keyReleased() {
186.   final int k = keyCode;
187.   if (k == 'D') {
188.     d = false;
189.   }
190.   if (k == 'A') {
191.     a = false;
192.   }
193.   if (k == LEFT/*left*/) {
194.     left = false;
195.   }
196.   if (k == RIGHT/*right*/) {
197.     right = false;
198.   }
199. }
201. class Player1 {
202.   float x;
203.   float y;
204.   float r;
205.   int frame;
206.   int flip=1;
207.   boolean block = false;
208.   boolean jump = false;
209.   boolean punch = false;
210.   boolean kick = false;
211.   Player1() {
212.     frame = 0;
213.     r = 30;
214.   }
215.   void display() {
216.     pushMatrix();
217.     translate(x, y);
218.     scale(flip, 1);
219.     image(bill[frame], 0, 0);
220.     popMatrix();
221. // checks to see what keys are pressed to show animation
222.     if ( (d== true || a == true) && (w==false && s==false)) {
223.       if (frameCount % 4 == 0) frame++;
224.       if (frame >= 5) frame = 0;
225.     } 
226.     else if (s==true && w==false) {
227.       if ( block == false) {
228.         frame = 9;
229.         block = true;
230.       }
231.       if (frameCount % 4 == 0) frame++;
232.       if (frame >= 13) {
233.         frame = 5;
234.         block = false;
235.         s=false;
236.       }
237.     }
238.     else if (w== true) {
239.       frame = 6;
240.     } 
241.     else if (drpdwn == true&&s==false&&w==false) {
242.       if ( punch == false) {
243.         frame=22;
244.         punch = true;
245.       }
246.       if (frameCount % 4 == 0) frame++;
247.       if (frame>=30) {
248.         punch = false;
249.         drpdwn = false;
250.       }
251.     }
252.     else if (cntrl == true &&s==false&&w==false) {
253.       if (kick == false) {
254.         frame=14;
255.         kick = true;
256.       }
257.       if (frameCount % 4 == 0) frame++;
258.       if (frame>=20) {
259.         kick = false;
260.         cntrl = false;
261.       }
262.     }
263.     else {
264.       frame = 5;
265.     }
266.   }
267. // player location and direction facing
268.   void move(float X, float Y) {
269.     this.x = X;
270.     this.y = Y;
271.     if ( d == true) flip = 1;
272.     if (a ==true) flip = -1;
273.   }
274. }