If you are brand-new to mining, NiceHash has a benchmark utility that will help determine what algorithm is best for your hardware, and the Windows mining client automatically switches to the "best" currency to mine. Payouts are all converted to Bitcoin. Don't expect to reach the minimum payout threshold very quickly, however.

As Mocacinno said above, don't expect huge proceeds from this, especially if you're only CPU mining (those integrated graphics aren't going to help you). If you have free power though, you may as well mine if you have no better use for so many PCs. (Although, if you have no better use, I'd have to wonder if you should just try to sell them and buy coins using those funds.)

Your hardware may or may not suffer significantly from this. Pegging your CPUs 24/7 puts more strain on your systems, so it's up to you if that risk is worth it. I personally don't think mining on laptops (I assume?) is a good idea, but it's your call. Laptops were definitely not meant to be pegged 24/7, but you might be able to figure out a cooling solution by messing with the cases.

-I have access to free electricity and a couple dozen Windows pc units. I'll post the specs at the end.
-What I want to know is, what is the easiest or most profitable cryptocurrency to mine?
-I do not have any money to buy any extra equipment or do any upgrades.
-Please point me to a guide on how to mine whatever you suggest.
SPECS.
CPU: i3-3110M 2.40GHz
Ram: 4GB
GPU: https://ribletjorb.tumblr.com/image/163358130871