re: Poker & "Betting"
Generally the standard raises preflop are 3-4x the BB + an additional BB for every limper before you.
So if you have AA on the button, blinds are 10/20, and there are 3 limpers before you and you would like to raise (which you should almost ALWAYS do preflop with AA) you would generally raise anywhere from 60-140.
On the flop a good bet is a consistent one, you usually want to bet similar amounts if you are bluffing, have a monster, or if your on a draw to further disguise your hand.
Generally a good flop or turn or river bet is anywhere from 1/2 the pot - the size of the pot.
If there is a nice medium-sized or larger pot and your have the nuts, you want to get paid off. Here you would make a valuse bet (a bet that the opponent pretty much has to call since it is so small in comparison to the pot).
For example if you hold 33 and the board is A-3-K-3-7 and you are fairly certain that your opponent is holding an A or a K you don't want to push all-in if you are certain that he will fold. If the pot is lets say 800 at this point, you want to bet as much as your opponent will most likely call with a second-best hand, this could be an all-in bet or a bet more around 200-400 in this example.