Why don't you have a password to get on your computer?
7 year old computer running Windows 2000 best time just under 3 minutes. When computer has many problems 6 minutes.
On my current build, about 15 seconds from cold boot to my account, Vista 64-bit.
I just learned that you can set your PC in Windows 7 to boot using all the cores on your CPU. I've changed mine from 1 to 4 and didn't see any performance enhancements
There is also this option in Windows Vista.