The limpreraise with AA or KK is a popular play here. And a good play if you know how to play it when no one raises.
How would you play it if you were UTG+1 (you have no reads)?

Party Poker No-Limit Hold'em, $6 BB (9 handed)

MP3 ($812.35)
CO ($595.5)
Button ($198.85)
SB ($615.74)
Hero ($555.95)
UTG ($379.15)
UTG+1 ($582)
MP1 ($493)
MP2 ($821.75)

Preflop: Hero is BB with , .
1 fold, UTG+1 calls $6, MP1 calls $6, MP2 calls $6, MP3 calls $6, 1 fold, Button calls $6, SB completes, Hero checks.

Flop: ($42) , , (7 players)
SB checks, Hero bets $30, UTG+1 calls $30, MP1 folds, MP2 folds, MP3 folds, Button folds, SB folds.

Turn: ($102) (2 players)
Hero bets $60, UTG+1 calls $60.

River: ($222) (2 players)
Hero bets $125, UTG+1 calls $125.

Final Pot: $472

Results in white below:
Hero has 5c 3h (three of a kind, fives).
UTG+1 has Ad Ah (two pair, aces and fives).
Outcome: Hero wins $472.

Since no one raised and i couldn't reraise....

i would raise your flop bet. If anyone calls that raise on that board...you have to think there's a very good possibilty AA is not winning the hand.

I would check the turn and pray the opponent checks the river...I might call a small value bet.

Yes, raise flop and fold to any action after that.

Like Kenny said, I would've raised your flop bet to see if you really had the 5, and would've been done w/ the hand if you stayed in the hand...

As the top of your post says "if you know how to play when nobody raises" , which he obviously doesn't... What the hell did he think you were betting w/ A7?

Fold the turn.

How could you fold the turn if you dont raise the flop? He very well COULD have A7. he could also have something like 88 or 99.

Raise the flop and then try to get to showdown as cheaply as possible after that.