I recently had some problems with my backup user's account (Dreamhost actually gives you 50GB of personal backup space). But this answer pretty much makes me want to leave… sadly, I don't think Dreamhost will give me a partial refund for the money already paid.
Just read the following Answer I got from the Dreamhost support:
Sorry about the continued inconvenience the backup issues are causing.
The problem is that the volume of the backup server where your user
stores its data is currently full. Our admins are working on distributing
the users and adding more space, but the very rough estimate I received
is that this won't most likely be done until the end of next week. There
is also some user misconfiguration issues going on, so that would explain
why you can't delete the files. Sorry about that.