Does anyone know if you can run Windows PE as general operating system in a home or business environment. I read at another forum that you cannot as it's only made for recovery purposes.

A quick search will tell you:

http://msdn.microsoft.com/en-us/library/ff794946(v=winembedded.60).aspx

Automatically stops running the shell and reboots after 72 hours of continuous use. The reboot timer cannot be configured. This constraint helps prevent the use of Windows PE as a general-purpose operating system. Windows PE is not licensed as a general-purpose operating system.

The "PE" in Windows PE/WinPE stands for "Preinstallation Environment", although with the advent of MS DaRT (Diagnostics and Recovery Toolset) back when Microsoft acquired Winternals, it can also be used as a rudimentary recovery environment (sometimes called Windows RE or WinRE - "RE" is Recovery Environment) that actually ships with Windows installation DVDs and gets installed when you install Windows Vista or higher. DaRT is a standalone toolset available to customers with a Premier contract and SA on their volume licensing for Windows that is a more fully-featured recovery environment built by Microsoft that runs on Windows PE.

If I just ran Microsoft Windows PE for personal use would I still get in trouble?

I can only answer your first question with Microsoft's official statement on WinPE:

Windows PE is not licensed as a general-purpose operating system.

Therefore, using it as such does violate the license for use. Getting in trouble for violating the license terms is relative, so I can't comment on that. You have to make your own decisions on whether or not to follow the licensing terms.

In any case, settings and configurations like those written to registry, are not kept over a reboot when in WinPE. It is only kept in memory.