A question about isolated pawn

If i have an isolated pawn in the center, should i try and keep more pieces on the board or try to exchange as much as i can? (or it doesn't even matter)

You want to keep pieces on because it will give your pieces more lines and activity as well as a slight space advantage.

If pieces are traded off it's normally a slight weakness in the endgame.

Keep them on the board. The isolated pawn may help you in the opening and middlegame, allowing freeing development and movement of your pieces but it will become a rather large weakness in the endgame.

Scott beat me to it.

Also, if you can advance it before it gets blockaded, you usually do quite well.

Thanks to all of you :D