I think that since Harry had been geared toward his own survival, he would never explored the forbidden corridor in which he had been trapped in.
First of all, the basic health and safety tips for people falling and trapped would be to not move around, because you wouldn't know where the rescuer will try and blast a way in; plus they will search in the near proximity of where you had fallen/ where the debris is. I think this Harry would know it.
Two, this Harry knew how dangerous and insane Hogwart is; Would he wanted to explore a dark tunnel which probably contain some inexplicable abomination waiting for unwary students? Heck, they sent a couple of first years to search a dangerous unicorn hunter/predator.
Three, you DO NOT try and light fire when you're near debris. God knows which pipe might have blown off or chemical spilled that would catch fire because of the cracked walls/ceilings. Again, safety tips which Harry would know. Especially when the school is filled with dangerous stuffs he still mostly didn't know about. Heck for all he knows there's some insects/moss that actually secreted gasoline or alcohol trapped somewhere around him.
So best choice, sit and wait. Sooner or later someone will come and find him. And the rescue would be easier if he don't run around.
Just my ten cents.
Eventhough I do like the part of, "Clearly this whole "evil speech" thing wasn't going as he'd planned."
In fact I think when Harry saw Quirrel barging in he would go, "Professor?! Wow! You're quite fast in saving me, I think the school's respond to emergency is getting better!"
Cheers!
Riani