Big Slick is breaking me--line check please

[TomorMatt]

I have not been playing at the table very long, but here are the stats on the Villian--17/8/1.8. This is a relatively small sample (337 hands), but seems pretty accurate. Anyway, here is the hand.

FullTiltPoker Game #435952349: Table Stonewater - $1/$2 - No Limit Hold'em - 18:16:22 ET - 2006/02/12
Seat 1: Hero ($136.15)
Seat 2: TexCTT ($183.40)
Seat 3: Scuba1127 ($152.20)
Seat 4: Villian ($175.40)
Seat 5: LadyCope ($400.10)
Seat 6: dmejias18 ($122.40)
Seat 7: kylepost ($187.75)
Seat 8: Nnnguy ($68.25)
Seat 9: TeraT ($208.25)
dmejias18 posts the small blind of $1
kylepost posts the big blind of $2
The button is in seat #5
*** HOLE CARDS ***
Dealt to Hero [Ah Kh]
Nnnguy folds
TeraT raises to $4
Hero raises to $12
TexCTT folds
Scuba1127 folds
Villian raises to $20
LadyCope folds
dmejias18 folds
kylepost calls $18
TeraT folds
GoQuakers calls $8
*** FLOP *** [5s Js Ad]
kylepost checks
Hero bets $116.15, and is all in
Villian calls $116.15
kylepost folds
Hero shows [Ah Kh]
Villian shows [As Ac]
*** TURN *** [5s Js Ad] [7s]
GoQuakers: nh
*** RIVER *** [5s Js Ad 7s] [2h]
Hero shows a pair of Aces
Villian shows three of a kind, Aces
Villian wins the pot ($294.30) with three of a kind, Aces

In retrospect, since the Villian is pretty tight I should have put him on QQ-AA with his raise, but when the A came on the flop, I weighted KK too much. Easy to see in retrospect, but seems like this type of player is going to fold his KK and call with anything that beats me. My question is if I should have lead with a smaller bet on the flop (somewhat difficult because the pot is relatively large) or if I am destined to bust here. My general problem is that I seem to be running into sets when I flop an A or K with AK and find all my chips in before I can assess what the other player is holding. I seem like a typical donkey that is so anxious to get it all in when I hit this flop that I am paying a heavy price. Certainly I have made money from bigger donkeys that call with AQ or AJ, but more often than not I am seeing a set or two pair. Any line to probe and lay this down without being to weak-tight?