I tried to post this yesterday. Do yourself a favor as I had a similar issue that a brilliant friend caught. If you have Partition Magic, boot from DOS and check your partitions. You may have a hole as I did which had a daemon virus lurking there. Reformatting the drive will NOT correct it. No antivirus will find it as it is not assigned. It is probably about 8MB in size. If it is the ONLY way to kill it is to low level reformat your drive. WD and others have a utility that does that. When I killed my Internet connection and network connection, I thought I was in a Steven King Novel as the virus kept banging on my floppy to escape. The symptoms were the same, except mine used 99% of the CPU through explorer. Same effect though.
I hope you don't have it. Only other thought is to kill ALL services you can and go into safe mode. If it still happens, then I bet that you have either a hidden virus or a real one. I'd boot from DOS with anything you have. It doesn't matter and then use Norton or another Antivirus product to check your MBR and your memory.
The Non partitioned issue is a know one which I understand has really never been published by anyone. I hope that helps. Low level formating and reinstalling is no fun. But it's better than where you are now.
Luck
