Yes, never ever upgrade from a release OS to a beta OS unless you are willing to format and reinstall (or put back an image-copy) when expiry date comes. Also not wise to install it like that if you have to rely on one computer!
Dual boot (install on other partition) is the wise choice if you do wish to try/test a beta OS -
How to Dual boot Windows 7 with XP or Vista (same one MenthiX linked too, he linked me to it before).
No need for BC edit tools, not yet anyway! But once expiry time comes and you want rid of Windows 7 you might want/need one to remove the Windows 7 boot entry (if you format the partition you installed it on, from release OS. Correct way to uninstall:
Remove Windows 7 from dual-boot with Vista). Install one on your current release OS installation for when the time comes/just in case -
EasyBCD
I have it set up like that and was mighty glad I still have Vista installed too, as my network adapter (Atheros L1, formerly Attansic) was not recognised and the driver disk would not install it on Windows 7 either (motherboard driver disk). So I booted back into Vista, downloaded driver installer from the internet, put that in the partition I use to store my installation files and documents, then back to Windows 7 and install. Imagine someone installing it fresh ("hey, fresh install is always better so let's wipe current installation") on the one computer they have and not have access to the Internet anymore!
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