The san pedro is not a san pedro in my opinion. Yours has distinctive "bumpy" areoles, which the san pedro doesn't.

Btw, nice IR background.

I don't know if it's active or not (its name), but if I had to bet, I'd say no.
The peyote looks like a peyote to me.

The "unknown" looks like a "Cereus Peruvianus" and is inactive.
The "San Pedro" looks like a hybrid of "Trichocereus Bridgesii" or "Achuma", which in my experience is one of the most active.

I recommend cutting about 12" off your cactus, make some syrup and give it a whirl.

That is not a true peyote. I forget the name of this species but I am 100% sure it's not lophora w.

hard to say at that age, look for pink flowers when it matures

In my opinion it does not look like an active plant, but looks like a sun starved cuzcoensis type. However without having seen it grown in brighter conditions it cannot be identified by me.

The peyote looks very cute.