It also wouldn't hurt to take an average. Since 60 Hz has a period of 16.66 milliseconds, and an A/D conversion takes about 30uSecs, you could average 16 samples (a full cycle) something like this:

Code:
   ADCAvg = 0            ; Clear the variable
For X = 1 to 16
   ADCIN,x, ADCresult
   ADCAvg = ADCAvg + ADCresult
   Pauseus 1000  
   Next X
ADCAvg = ADCAvg >> 4    ; divide by 16
This should do a pretty good job of smoothing the result.