If I Build A Custom Computer Can I Install Windows 7 Without?
If I build a custom computer can I install windows 7 from the start, or do I have to install a different OS in first, also when the time comes, how do I remove windows 7? Do I just put my OS disk in?

You could install the Windows 7 Release Candidate from the start, but it expires in early-mid 2010. You’d need to have it available in advance on disc or a bootable USB drive though.
If you want to remove it later, you’ll need to reinstall over it with another OS disk.
never ever use upgrade. just do a clean install every time. dont go from vista to windows 7. and just save ur files and u can do the clean install easy. yeah btw the final product windows 7 will be released this December.
You can install Windows 7 RC just download,create an image on dvd and install.
It will let you reinstall vista or xp I have installed xp over it by accident and it did not complain.