My thoughts ...
I love disc brakes, but they can be a pain to keep adjusted properly. The stopping power and feel of a good set of disc though...incredible.
For now, you might want to get the v-brake model like others have suggested and upgrade in the future if you'd like. FWIW, I just bought a set of Avid Juicy 5 on ebay for $114. It was a steal but those kinds of deals exist, so upgrading to something pretty nice won't be that tough.