re: Poker & Late tournament play!
Olddog, you're leaving out a lot of information. When you've been pushing all-in, was it preflop/postflop? Were you in position or not? What was your stack size in relation to the blinds? Your opponent's stacks??? All of these come together in explaining whether you made the right play or not.
If you had a short-mid stack and it folded around to you and you pushed allin with say ~6BB left preflop....in all of your situations above, you made the right play.
Same stack, but before it gets to you someone else pushes first, you might want to think about folding your hand, depending on how tight and/or aggressive they have been.
Once it goes post flop, you could be in some trouble, depending on how preflop went. Did you let a lot of people in cheap? If so, any aggression could mean that someone made something like top two pair on a raggy board. In that situation, it would look great for you because you'll think, "Hey, I have all of the pairs on the board beat...", but not the 2 pr. If any card higher than your pair hits the board, the same thing happens if you let a lot of people in cheap.
fact of the matter is, no matter how good you end up getting at poker, your AA and KK will still get cracked from time to time, your sets will lose to higher sets and maybe if you're lucky, you'll have the idiots end of a straight flush and lose to the higher end.... nothing can stop it, but by playing and learning as much as you can, hopefully you won't lose as much/often with them.