|I don't know where you have the computer currently located. If it is located in a computer desk cubbyhole I suggest you stop running it in there. Most desks like that do not allow for adequate air circulation.|
Nothing that is on your hard drive can cause the computer to hang prior to Windows initiating. From what you have described I don't think it is getting to that point.
Do you eventually see a Windows splash screen? If so, is it the very next thing that appears after the hang?
I suggest you download and run from the boot disk a memory test program. Memtest 86 is one such program. You can get it at the link below.
One thing you could do to troubleshoot is to remove three of your hard drives from their caddies temporarily and try booting to just one. If the computer doesn't hang then you will know the problem is with one or more of the other drives. If it still hangs try each drive, one by one.
If that issue is eliminated I would next suspect the power supply.
Rereading your posts you state that WinXP doesn't work right. What happens with it? Does that drive always show in the BIOS?