5 Card Draw, Dealt a Pair

So i was wondering what the appropriate way to play a hand in which you are dealt a pair...
Lets say youre dealt AAJ34

Is it right to discard the three cards and shoot for a set, or just discard the 3 and the 4 and have a shot at 2 pair or the set...

It seems it would be better to hang on to one card so that youd have 2 shots at five outs, rather than 3 shots at 2 outs. I know in holdem you pretty much have a 2 percent shot at each out per draw... so for the five outs with 2 shots, thatd be an 8% chance of getting trips (or is it called a set here?) and a 12 percent chance at 2 pair.
In the other situation you have a 12% chance of a set, and little chance of 2 pair.

So it would seem that it makes sense to discard the two cards...
It would even seem to make sense if you had AA237 to discard the 2 and 3 under the above logic. Is it good logic? Also, it disguises your hand a little more because when someone discards 3 cards, you know they have a pair - also if the above logic is correct, these people would be wrong in discarding 3 cards in either situation.

Discard 2, keep the p' Aces & Jack. Bet at least 1/2 pot to drive off weak chasers, pot if you know you'll take it down right there from how the villians play their hands.

Strong betting before the draw will take down the pot right there more often than not in 5 card draw. If it doesn't you're still in pretty good shape but keep a very close eye on how many cards each villian still in the pot discards. (something you should always watch even if you fold a bad hand to make good reads on your opponents in future hands)