1-2 NLHE, villain starts hand with ~180, Hero covers. Don't know much about him and haven't seen him over-bet yet, but he has done/said some weird things.
Hero straddles to 5 (standard in this game, don't know why), and i know how people feel about this but anyway...

3 callers, button raises to 20.

Hero calls with AJo (anybody fold here, call feels pretty standard to me)
all others fold

Flop: AT3 rainbow

Hero checks, Villain bets 80 (into about 65)

Hero?

Against a complete unknown in this spot,

its a fold.

If villain's range is AT-AK you are dominated. Most 1/2NL players do not have it in them to overbet an Ace high board with JJ-KK.

In these spots, its always a good idea to fall back to basic ABC play until you pick up more info on your villain. He could be a complete donk or a giant nit. You just don't know...

And yes, don't straddle.

so yeah, easy fold here.

Snap fold and it's not even close.

Since you aren't sure what to do now, that means you should have folded preflop.

A rare, intellligent post on 2 plus 2.

i did fold an he showed A3, i was just making sure I wasnt making some terrible play here

Preflop: I'm not sure exactly what you mean by saying the straddle is standard, but the effect of it is that you're making the game play extraordinarily short. You've turned the effective stacks from 90 BBs to 36 BBs, so you'll have to adjust for that by shoving lighter than you would with 90 BB stacks.

As for the play of the hand, I would also call. Button's raise is very weak, he's only raised 4 BBs after 3 callers and he's doing it from the spot where he's most likely to be screwing around with a non-premium hand. AJ is ahead of most of his range. If you were 20 BBs deep a shove is automatic, but a 3bet of any size here is problematic because you're essentially committing yourself to an all-in in a spot where all you stand to gain is 7 BBs. The fact that you're out of position doesn't matter because the stack sizes dictate that the money will go all-in almost every time you hit top pair.

Flop: The flop is so dry that it's probably best to just check/call and hope that villian will keep firing if he has a worse hand than AJ. If you fold anywhere up to this point your poker player's license should be revoked.

Just my opinion...