[JFreak]

Let's see; if you only have a 2-channel mBox, then you naturally have a dramatic limitation to be dealt with. You can have either:

1) good stereo image that lacks punch
..or..
2) good punch without stereo image.

Given the music style you mentioned, perhaps the punch is more important than stereo image? If so, then use one channel for kick and put another mic near snare. I don't mean the usual close miking of snare, but place the overhead a lot closer than usually, and point it towards snare. That way you should get "everything" you need. After recording, give kick the usual treatment and then spend a lot of time EQing the oversnare track.