i'm trying to use a microphone with Abelton. i have an Mbox2 and when i plug everything in, the program recognizes the mic input(the peak limiter lights up when i speak into it) but i can't hear anything. does anyone know what i might/might not be doing?

Make sure you have set up your audio preferences correctly. You go into options--preferences--hardware config and inputs and outputs. Make sure that you have your I/O enabled (they would light up green).
Then make sure that the output of your MBOX is the output track on your Master channel (the one all the way to the right).
When the peak limiter lights up, are you saying this is on your MBox or on your Ableton Live track. Don't forget that to hear any input, you need to arm your track (and have monitoring on Auto) or have On selected on monitoring.