Yeah, but if you feel the freeze was done in an error, you can email them and get your acount back, this usually only works if you DIDNT do anything, if you did break a rule, the chances are next to nothing of being frozen
If you're frozen, it's usually permanent unless it was error on their part. You can be suspended for a certain an amount of time if you break less important rules. Those usually have something to do with the boards.
Just use some common sense, and don't be too greedy when using the programs and you'll be fine. aka - dont leave them on overnight.
If you use it long enough you're bound to get atleast 1 account frozen (unless you're lucky) But that is what proxys, and side accounts are for