Using a hole saw without breaking my wrist

So I bought a 2 in hole saw and drilled 5 holes. Once it got to the very end of the cut the drill would jerk violently. I could have easily broke the drill or worse. While drilling into the butcher block it smelled like it was going to catch on fire. I'll know in the future I should take breaks, so the bit doesn't get too hot.

I'm considering a portable AC unit and would want to drill vent/intake holes into my box van roll up door. The roll up door appears to be some kind of laminated metal sheet on both sides with 1in of wood in the middle.

I would only feel comfortable attempting this with a drill that has two grip points or something that mitigates the jerking; the trouble with my regular ryobi drill is there's really nowhere else to grip the thing with both hands.

Do I need a hammer drill, an impact drill, or some other drill (or some other tool)? It's not worth the risk of self injury to use my current drill with the hole saw, for regular drill bits though I've had no issue.