lm34 math

Using a lm34 for temp, don't have vref pin so using 5vdc full. So if I take 5/1024 (using 10 bit because already using in another part of program) this gives me steps of adconversion? So that said if temp is 40 deg I would take .4/.005 to get digital output?

You use the operational amplifier to get the output 0-5V.
If you connect the output directly to the pic, you will lose the accuracy.
You can try this T = (500 * ad_res) / 1024