Some usual suspects to check: dodgy files in your autoimport folder (empty it), dodgy queue item (clear it), corrupt queue (delete queue files from \misc), bad file permissions (reinstall, disable UAC or run as admin), etc.
I had exactly the same problem as the OP - I was noticing that my system was crashing sometime after I started Alt.Binz, despite using it for a long time and never having a problem. I looked on task manager in Windows 7, and found that Alt.Binz 0.31.6, even when I wasn't downloading anything, was leaking memory like nothing on earth - even getting into the gigabytes of memory usage.
Clearing the NZB import folder and the download queue fixed it - it then stopped leaking memory, and worked perfectly.
Thank you for the suggestion!
