Joshua,

Since you are using the R0 thru R7 registers, in order to get known delay, you would have to initialize the registers before calling the delay routine. Also 2 seconds is much too long for switch debouncing, 0.2 seconds would be a better choice.

I would suggest that you pick a delay time such as 1 second and initialize the R2,R3,R5,R6 values accordingly.

Jacob