Mouse and computer seem to have lost connection

I have a Dell XPS desktop with Vista Home Premium. I was on it earlier today and everything was fine.

When I came back to it this evening the screen was black and I couldn't get it to wake up. I finally pressed the power button and my desktop came up.

SUPERAntiSpyware was open on the desktop and running a scan. My wireless Logitech mouse had no power. I pressed reset and all that, even changed batteries. Then I got down two other Logitech mice I had, which both work. Same thing with them.

I pressed the power button and the computer shut down. I let it set for 10 minutes and restarted. Still nothing.

I noticed that I kept getting that sound that is made when the add or remove new hardware is active, and I noticed that the Add New Hardware icon appeared in the taskbar. Of course, nothing had been added.

If anyone help me out here I'd be real happy to hear from you. Good thing I got a new Toshiba laptop for Christmas, however, there's lots of stuff on my Dell that I want access to, and the computer appears to be working fine. I just can't get any of my mice to connect.