I don't know whether to like or dislike my play on either of these--I guess I have to dislike the pure check-call. But I wanted to throw them out there, just as part of the discussion:

In the first one, I felt like my opponent was very inclined to make plays, and the turn looked pretty blank to me--of course, he could have made 2 pair...

Well, blast, hand converter seems to be down, so I'm just going to copy the raw data:

POKERSTARS GAME #4272443315: OMAHA POT LIMIT ($1/$2) - 2006/03/13 - 05:04:14 (ET)
Table 'Kleopatra V' Seat #2 is the button
Seat 1: junebug2003 ($137.05 in chips)
Seat 2: jp386 ($127.10 in chips)
Seat 3: And!Baller69 ($109.05 in chips)
Seat 4: Hero ($212.15 in chips)
Seat 5: andersCleanU ($209.40 in chips)
Seat 6: woftam111 ($36 in chips)
Seat 8: vesap ($96.60 in chips)
Seat 9: Justice4all ($62.85 in chips)
And!Baller69: posts small blind $1
Hero: posts big blind $2
vesap: posts small & big blinds $3
*** HOLE CARDS ***
Dealt to Hero [Kd Ad As Jd]
andersCleanU: folds
woftam111: calls $2
vesap: checks
Justice4all: folds
junebug2003: calls $2
jp386: calls $2
And!Baller69: calls $1
Hero: raises $13 to $15
woftam111: folds
vesap: folds
junebug2003: folds
jp386: calls $13
And!Baller69: folds
*** FLOP *** [3h Tc Js]
Hero: bets $12
jp386: calls $12
*** TURN *** [3h Tc Js]
Hero: checks
jp386: bets $60
Hero: raises $125.15 to $185.15 and is all-in
jp386: calls $40.10 and is all-in
*** RIVER *** [3h Tc Js 5s]
*** SHOW DOWN ***
Hero: shows [Kd Ad As Jd] (three of a kind, Aces)
jp386: mucks hand
Hero collected $260.20 from pot
*** SUMMARY ***
Total pot $263.20 | Rake $3
Board [3h Tc Js 5s Ac]
Seat 1: junebug2003 folded before Flop
Seat 2: jp386 (button) mucked [7h 9c 7c 5d]
Seat 3: And!Baller69 (small blind) folded before Flop
Seat 4: Hero (big blind) showed [Kd Ad As Jd] and won ($260.20) with three of a kind, Aces
Seat 5: andersCleanU folded before Flop (didn't bet)
Seat 6: woftam111 folded before Flop

Noteworthy is that I didn't need the additional A.

Here's one where I got much too cautious:

POKERSTARS GAME #4272305532: OMAHA POT LIMIT ($1/$2) - 2006/03/13 - 04:18:09 (ET)
Table 'Kleopatra V' Seat #6 is the button
Seat 1: junebug2003 ($127 in chips)
Seat 2: Hero ($339.75 in chips)
Seat 3: And!Baller69 ($183.05 in chips)
Seat 4: newplayer06 ($121.75 in chips)
Seat 5: andersCleanU ($263.55 in chips)
Seat 6: Qcity1 ($192.35 in chips)
Seat 8: iron81 ($208.80 in chips)
Seat 9: Justice4all ($58 in chips)
iron81: posts small blind $1
Justice4all: posts big blind $2
*** HOLE CARDS ***
Dealt to Hero [Ah Ac 6s 2d]
junebug2003: calls $2
Hero: calls $2
And!Baller69: folds
newplayer06: raises $9 to $11
andersCleanU: folds
Qcity1: folds
iron81: folds
Justice4all: calls $9
junebug2003: folds
Hero: raises $36 to $47
newplayer06: calls $36
Justice4all: folds
*** FLOP *** [4h 2c 9h]
Hero: checks
newplayer06: checks
*** TURN *** [4h 2c 9h]
Hero: checks
newplayer06: checks
*** RIVER *** [4h 2c 9h 9c]
indocott joins the table at seat #7
Hero: checks
newplayer06: bets $16
Hero: calls $16
*** SHOW DOWN ***
newplayer06: shows [8d 5d 5c 8s] (a full house, Fives full of Nines)
Hero: mucks hand
newplayer06 collected $137 from pot
*** SUMMARY ***
Total pot $140 | Rake $3
Board [4h 2c 9h 9c 5s]
Seat 1: junebug2003 folded before Flop
Seat 2: Hero mucked [Ah Ac 6s 2d]
Seat 3: And!Baller69 folded before Flop (didn't bet)
Seat 4: newplayer06 showed [8d 5d 5c 8s] and won ($137) with a full house, Fives full of Nines
Seat 5: andersCleanU folded before Flop (didn't bet)
Seat 6: Qcity1 (button) folded before Flop (didn't bet)
Seat 8: iron81 (small blind) folded before Flop
Seat 9: Justice4all (big blind) folded before Flop

This hand was actually the reason I switched to making a weak probe bet rather than just checking and hoping.

Would you call a raise on the button with AA?

If so, is it better to have a raised pot or an unraised one?

In contrast to HE, however, I think the best way to deal with raises is simply to try to play it (if you raised) simply as if someone else had raised in the same situation.

The re-raises I'm still not at all sure about. Maybe they're just not good unless you're playing a table where the re-raise callers have more well-defined holdings. I thought bri's Q96 flop was pretty illustrative. In analysing it, that seems to be a pretty dangerous one against players who are only going to play truly premium hands to the re-raise.

If you're going to re-raise, then I think it's almost more about reading the board than about anything else--and if your opponent can have almost anything, reading the board is kind of a pointless exercise, too.