Why the center?

My openings (Nf3 and b3) do not directly place a pawn in the center the common openings (D4 and e4) do, yet most of the games I play, I win. So why the center with a pawn (the weakest piece)

???

http://video.google.co.uk/videoplay?docid=-7532720083682832362&ei=DgArS-T5FYaO-Ab84OTLAw&q=the+importance+of+the+centre+in+chess#

http://www.metacafe.com/watch/2795903/the_center_in_chess_part_i/

My guess would be most of your oppenents don't understand that an early control of the center can lead to good positional play, and probably focus on looking for tactics while not improving position which can lead to big disadvantages. I know personaly if I play someone my playing strength and I'm a pawn down I usally have a tough time compensating if we make it to the end game. The only times I lose a pawn is complete carelesness and bad positional play.

I think the pawn is placed there to ensure maximum movement of the pieces. However, though they say that white has the initiative at the start, doesnt it just give the opponent the initiative by giving them a target? (the undefended pawn in the middle of the board) So maybe thats a factor in your games - the lack of a target.

1.Nf3    and 1.b3     are perfectly fine

The center may be controlled by occupation or by influence.  Thus both e4 and Nf3 are played with an eye to controlling the center.

pawns are good center pieces because they are not worth much so they can't be kicked. They are easy to defend and occupy the center as well as anything.
Playing your openings usually precedes counterplay for the center

The moves you played ARE moves for control of the centre, just using pieces rather than pawns. They're very well-known and perfectly sound openings. Nothing unusual about them at all...

EDIT: BTW, I think you meant 1.b3 rather than 1.b2.

1. Nf3 and 1.b2 (beginning of the Nimzowitsch-Larsen attack) both plan to occupy the center the first one directly and the latter by fianchettoing queen's bishop. They both are playing into the "hypermodern school" of chess.

Of course 1. b2 is ultra hyper modern as it is not a move.

1.b3 does focus on the center, because you are fianchettoing your bishop on b2 and the a1-h8 diaganol your bishop is on crosses right through d4 and e5 helping to control the center. Mostly the goals in the hyper-modern openings is to let your opponent get a big center only to crush it later on. Also on 1.Nf3 (which can transpose to the english if you play c4) also develops towards the center and the knight on f3 hits the d4 and e5 squares as well. Also if you're wondering why the center is the most important to control, watch some videos and get some books like "my system" by Nimzowitsch. Nimzowitsch also believed in controlling the center with pieces instead of pawns. So good luck in your chess journey and for now judging by your rating don't spend too much time worrying about openings, spend time studying tactics and your chess will improve a lot. If you make a mistake in the opening take some time to go over your game and see what move made you lose and why. Just don't spend all your time studying the openings, there is no point at your current level.

At 1100 you win most the games you play?  Who are you playing? 

The reason pawns rather than pieces are placed in the center is that they are weaker than pieces, so if defended they cannot be captured by pieces. Placing the Queen in the center is usually not a great idea in the opening. Anyway 1. Nf3 is nowadays quite a common move but I would guess that your opponents don't know this.

I am really around 1300, that is my chess.com rating

Quick side note, if you win most of your games, you're playing people lower rated than you are most of the time (or your rating hasn't caught up).  Nothing wrong with that, but it's not a good basis to make a decision about whether a part of your game is working well.  Since they're not as good as you in general, they're probably not punishing your mistakes as much as somebody a bit better than you.

To improve, it's more effective to look at why you lose to higher rated players, and fix those problems with your game.

On your main topic of openings, there's always the surprise factor, especially in blitz games.  On short time controls, I usually play the English as white (most common 1. c4, 2. Nc3, 3. g3, 4. Bg2).  Most of my opponents aren't as used to playing against it, so they have to think about every move where as I'm playing out a routine.  With the English there's the added bonus that the first moves can be done almost without regard to what the opponent's done.

On short time controls, surprise is worth quite a bit, if the play is fundamentally solid.  Getting both can be tricky though. ;)

Everybody (except 100-500) win most of their games (and I do play higher rated players)!!!

cause your 1300 anymoves work good ;D

With ELO (and ELO-like) ratings, your win ratio correlates pretty directly with how many lower rated players you play against*.  If it didn't, your rating would move with the wins until it was true!

But I didn't mean to imply that you only play against lower rated players, or even that there would be anything wrong with that.  Only that when you're trying to determine the strength of part of your game, it's more helpful to see how it fares against players stronger than yourself, as they're more likely to see any weaknesses and be able to punish you for it.  Easy to say, I know!

*math nitpick:  not taking draws into account, and assuming a relatively smooth distribution of opponent ratings. 

1 b3 is ok, but it allows black to get his fair share of the center, so he won't be behind in central space and can get his pieces out, which is good because in other openings he's under more pressure to achieve that goal. 1 b3 may not give black an advantage, but he doesn't have much trouble equalizing either. By moving a center pawn out right away you not only take space, but your pieces can go to active squares, while with 1 b3 e5 black can take space and block the bishop for the time being, giving white less chances for an initiative.

pawn in the center is not necessary. control of the center is what is important.

1. Nf3 controls d4 and e5 squares

1. b3 2. Bb2 controls d4 and e5 as well