Windows 7 was very troublesome to install on my system. My system specifications:
Motherboard: Biostar TF8200 A2+ (nVidia chipset)
Processor: AMD 4080e Athlon 64 x2 (45W version)
Optical: Sony/NEC SATA DVD-RW
Hard Disk: Seagate SATA 320GB, 7200RPM
Installation would hang at the "Starting Windows" logo. By pressing F8 when the installer first loaded, and selecting "Safe Mode With Command Prompt", I was able to see that it was hanging after loading DISK.SYS.
I experimented with SATA and AHCPI modes. I replaced the old PATA/IDE DVD-ROM drive with a new SATA one. I tried removing one of my 2GB memory sticks. I tried both the x64 and x86 versions. None of these changes made any difference whatsoever
In the end, the only thing that worked was to turn off all motherboard accessories. I believe I only needed to turn off the USB 2.0 controller, but to be safe I turned off all USB, audio, parallel port, floppy drive, etc.
Now that Windows 7 is fully installed, I'm still unable to use the USB 2.0 functionality.
As an aside, I reinstalled the OS two more times because I kept getting a black screen with the "Windows Release Candidate Build 7100" in the lower, right corner. After several frustrating hours, I realized that the problem was simply that I had both the VGA and DVI connectors plugged into my monitor! The installation had been continuing just fine, but on the other monitor input!