Vista user keyboard and mouse won't work

Yesterday I was trying to put some music on my Shuffle. was able to download from my playlists in ITunes, but I asked my son where I could get more music. He went to Torrent and we began to download some Led Zeppelin. The download took what seemed like forever. I had the Shuffle plugged into the computer, but I wasn't downloading to the Shuffle, it was just still plugged in we were just downloading to a file on our computer. I did turn an on/off switch button on the Shuffle and the computer made a plunk sound. I thought it was because I messed with this button. I then took the Shuffle off to listen to what I recorded so far. When I went back to the computer, the screen saver with the Microsoft logo was floating around a black background (which I've never seen before, if we leave the computer on, the screen just goes black - no Microsoft logo floating around. So then I tried to move the mouse to see if the screen would come back and it wouldn't. I physically turned off the computer and restarted it. Now the keyboard and the mouse won't work. The computer comes up, but it won't allow me to type or mouse to the area where we type our password to enter our desktop. With you being an IT dude, do you know what might of happened? I tried many times to shut down and re-start, then the computer tried to recover, but because the keyboard wouldn't work, I could not advance the screens to move forward with the prompts. We have McAffee, so I would think it would save us from any viruses. Any ideas?