Black Screen w/ Cursor and Watermark in Right Hand Corner

Hey guys, I've searched around for several weeks for a solution to this problem and have not yet found a solution that works for me... Here are some details...

I am running Windows 7 RC (Build 7100) on an extremely capable PC, but now, every time I start the machine up I get a completely black screen with cursor, and in the bottom right hand corner is the watermark,
"Windows 7100
This copy of Windows is not genuine."
I believe I know what caused this. When I first got the RC, I downloaded one of those patches that removes the watermark (Yes, I know I was stupid and shouldn't have ) and for awhile, everything worked fine. Then I found the above watermark sitting regularly on my desktop, as well as some "This copy of windows not genuine" Pop-ups from MS, so I clicked on resolve, and the MS website just said something to the tune of "This Windows OS is not yet supported" or something like that. So I didn't pursue the problem any further. Now, every once in a blue moon it will let me access the desktop. When it does, everything is extremely slow, I can't use command prompt, and when I open control panel to look at my CD Key or to check that it is activated, in the spot where my CD Key should be, instead there is just this: ---

Sooo, I need to know how to re-activate Windows so I can actually use the computer again. Any help would be appreciated. Also, I can give any information you guys need. I really hope I can get this resolved soon, it has just been such a hassle. Thanks guys!

Stephen

How about reinstalling the RC? It's not like at some point you were not going to do this anyway once you get the RTM.

True, I could do this, but is there anyway to do that without wiping the hard drive? Because if there isn't, I want to try all the other solutions I can find first, because I don't see a way of transferring my data to a different hard drive, though if there is, I would be happy to learn of it....

You could use a Linux Live CD to boot into your PC and transfer your data to a USB drive or another partition.
Or, I wonder if the Repair Windows option would work by booting the W7 DVD? Worth a look, anyway.

Yep, the Linux Live CD would be a good way to get your data off the machine. UbuntuLive is a good start:

http://www.ubuntu.com/GetUbuntu/download

I'd be interested to know if the repair install does fix the problem, so if you try that first please do report back .

Oops, sorry, I meant to mention that I already tried the repair install... It didn't detect any problems. If no one has any ideas of what I could do without re-installing Win7, I will get my data off tomorrow and do a fresh install. I already have a Ubuntu 8.04 CD, but I don't know if it is a Live CD or not. If my memory serves me right, it is, so I will give it a shot tomorrow should no new ideas arise. Thanks for your help, guys!

In addition to Ubuntu, Knoppix is a good choice. Just wanted to mention it here as an option.