This is sad sad sad - I am having the same issues and as another poster said - it has been happening for years. I have a rather new Sony VAIO with 64 bit vista. My daughter plugged in an HP digital frame to charge it and I can no longer use any USB port - except of course for the HP frame : (
I need a mouse but I really do not want to reinstall to factory settings because I do a ton of software development and ... it would take weeks to get back to my current state.
I bought a mouse today that uses its own drivers thinking that may help but to no avail. I am going to try the suggestion to power down, unplug, remove battery and so forth. I will let you know how it goes.