[Wlug] invincible processes

I just had some strange stuff happen to my SuSE 8.2 installation - it's stalling when I try to copy files and run some programs. If I try to kill the process, it doesn't go away (kill -9 pid, as root), and the machine won't shut down because stuff is still running. This coincidentally happened the same day that I started to prepare a replacement hard drive, so it's not on a critical installation (in fact, it's going to be wiped), but I'd still like to know what's going on. Note that I totally disconnected this drive when I was installing on the new one, just to make sure I didn't do anything to hurt it. Any ideas on what this could be or where to look would be appreciated. Greg