troubling common situations

[man]

I just began playing at the 10-handed Party $25 NL tables, and there's a bunch of situations that I keep running into that have caused a pretty big dent in my bankroll. These are probably pretty elementary, but I'm pretty elementary, so bear with me. I don't have the hands memorized, so I'm just gonna give a general outline of each situation. I've been multitabling, so I rarely have reads on the players. (Also, should I stick to one table until I've gotten the hang of things?)

Sitch #1: I get AQs UTG and open raise to 4xBB. Fold to CO/Button, they reraise to 10BB. Fold to me. Every time I call here, it seems like the only "clean" flop for me would be a flush draw, and that I'm easily behind if an A or a Q hits. And of course, I'm out of position. Should I lay it down? Do players at this level reraise with JJ, TT, or 99 often enough for it to be worth a call? Is it even worth a call if so?

Sitch #2: I open limp in MP with some trash like QTos, one late position player calls, and the blinds complete & check. Flop comes QT6 with two spades. Check, check, I bet the pot, LP calls, blinds fold. Turn is a blank, I bet (how much here? Pot? 1/2, 3/4 pot?), LP calls. River is a low spade, I (check?), LP bets 1/2 pot. Easy fold? I find myself paying off a lot in these situations, and it usually makes me feel fishy. (Side question: If the same situation occurs with an apparent straight draw, is my play any different?)

Sitch #3: I feel awkward on all streets during this kind of situation. I get 76os in the BB. Two limpers, SB completes. Flop comes 974 rainbow. Check, I bet (?) 1/2 pot or pot, one caller behind me. Turn is a blank. I bet again (?), he calls. River is a blank. I check (?). Any better way to go about playing this kind of hand?

I feel like my descriptions of the above situations are a little vague, and that I'm not giving you guys enough info. But I don't really have much info to go off of in these situations myself. I appreciate any input.