I had this same problem, where I'd have to hit ctl alt del to fix it temporarily. I updated windows fully and still had the issue. However I spent 3 hours looking for a fix and its NOT A MOUSE PROBLEM. Its apparent on all mice because its a usb root hub power saver option problem. Here is the solution and it actually works.http://forums.logitech.com/t5/Mice-and-Pointing-Devices/Fix-USB-Mouse-for-Vista-and-Windows-7-Freeze/td-p/404740
since I did this I have no problem at all. I hope this works for you also.