No need to reinstall just repair. Then you keep your docs programs and all that it just redoes the parts of windows that would be messed up.Yep, its just driver/hardware conflict most likely.
Windows does not like being taken from one machine to another and will quiet often protest.
Best to reinstall IMO.
Nope safe mode doesn't work, how can I back up my stuff when I cant login?
A linux live cd, boot from it and then copy all the data you want to some removable drive, Done.
I suggest ubuntu.
What's the password?Can you boot in safe mode?
Uninstall the drivers installed by that CD f oyu can.
If all else fails, boot of a boot disk and backup what you need.
Format HDD, reinstall Windows.
Try this boot disk: http://minipe.org/MiniPE.v2k5.09.03-XT_25_JUN_2008.rar