Such nutty things seem to plague upgrades. I learned long ago for upgrades to uninstall all I could before the upgrade. Especially any software that burrows deep into the OS such as antivirus, firewalls, CD/DVD burrners and a long list. The less installed the more successful the upgrades.
Have an AMD Athlon 64x2, 2.1 gig processor, with 3 Gig ram, and AMD Radeon X1250 onboard graphics.
Upgraded from Vista Home premium 32bit, to Windows 7 Premium 32 bit.
All drivers up to date except graphics, which AMD is not offering a Win 7 version update. Worked fine with Vista though. No malware or viruses.
Have the monitor set to turn off after 15 minutes, no sleep or hibernate enabled.
Using a Win7 "basic" theme, all is well.
When using an "Aero" theme, and hiding the Taskbar, I can move the mouse, wake up the monitor, and move the cursor. But that's it. Can't do anything else, even Ctrl, Alt, Del, for about 5 minutes, then all works fine.
If I DON'T hide the taskbar, this does not happen.
I prefer to hide the taskbar, so I just stick to the basic theme, but would really like to find out why this happens, or if anyone else might have the same problem.