yammata684 Wrote:Safe mode wouldn't come up...
All I get is a blinking cursor. No prompts, no menus, no safemode, no error message, nothing (cries for hours)

If the Windows boot screen doesn't show up, I don't think it's a registry issue (unless the entire registry is corrupt) - what you edited seems like a shell level entry, and that's loaded long after most of Windows is loaded.
Windows loads drivers and stuff during its loading screen, so something seriously is stuffed - I think something other than your registry edit is causing this...

yammata684 Wrote:Also I tried to access the registry editor today. It gave me access to HKEY_LOCAL_MACHINE\SAM, HKEY_LOCAL_MACHINE\Security, HKEY_LOCAL_MACHINE\System. The registry editor lets you choose where the registry is relative to the system directory. I need to know how to access edit HKEY_CLASSES_ROOT (or HKCR). This is where the keys I changed were. I need to know what to type in when it prompts for the directory. If I leave it blank it gives me access only to HKEY_LOCAL_MACHINE. Any ideas?

The Windows registry only really has two true root keys, HKEY_LOCAL_MACHINE and HKEY_USERS.
HKEY_CLASSES_ROOT = HKEY_LOCAL_MACHINE\SOFTWARE\Classes


Having a second install of Windows is indeed useful though.