Virus Sound Familiar to Anyone?

(Writing from another PC.)

My PC has a virus, I'm pretty sure. I turned it on today and my startup page with the password to get in was gone. It went to the default background (like Teletubby Land). All my desktop icons were gone (that I added). Only about six desktop icons were there including a program I installed just a few weeks ago.

When I opened Internet Explorer it brought me to MSN homepage (that is not what I had set).

It looks like all my installed programs, or most, are gone.

As I was checking pop-up's would come up from my various former programs like Google Calendar asking me to hit the button to install it. Other ones wanted my user name before it could install.

I only had the PC on for about two minutes (or less) before I did an emergency shut down.

The thing is I have a hardware firewall plus anti-virus software set to autoscan. I haven't had any notices lately that anything has been detected.

We did use a flash drive (ours) which had been used on someone else's laptop. We haven't installed any new software in a few weeks.

My PC will sit there untouched until my husband gets home from work when he can check it out.

If this sounds familiar to anyone let me know the virus name. I have been searching on the Internet by symptom to see if I can find it and so far only w32silly sound like it (low risk).

I have not backed up my hard drive in about six months (shame on me). So I have lots of documents with data and my writing that may be lost.

It is going to kill me to worry about this all day and not to be able to start diagnosing this!

ARGH!!!!!

Update: In the evening we turned on the computer to fix it and it is perfect. My husband thinks it's related to my PC doing an automatic update. I am so relieved.