Windows Vista will not boot after SP1 update attempt?

I have a Windows Vista Home Premium desktop computer. I recently just attempted to update to Service Pack 1. However, something went wrong. It went through the installation fine until the very end where I received some sort of error. I did some reading and apparently there is an issue with the update itself. I cannot even boot Vista up at all. Not even in any type of safe mode. I inserted my Recovery Disk (not installation disk, I lost mine, besides formatting is not an option for me as I have VERY important school files on my hard drive.) and nothing seems to work. It just goes on an endless loop. After the so called "recovery" attempt, I just try to boot up and I get the same issue. The loading bar just continues to keep going endlessly, or it attempts to finish installing SP1. I have exhausted everything in my power to fix this issue. I have tried booting in safe mode, which will not work at all. I have tried a system restore, but it only gives me the option to restore it the the very moment I tried installing SP1, and it won't even work. I left it alone all night (8 hours) and came back in the morning and it was still trying to "finalize" the system restore. I have tried command prompt through the recovery disk to attempt to fix it using an online tutorial. That did not work either. Nothing seems to work and as I said, I do not have my windows vista installation disk that came with my computer. It has been lost in a move. What am I to do. If you suggest something, chances are I have tried it, but forgot to mention it. I really am at my wits end and don't know what to do. Please help me. Apparently this has been an issue for many people due to microsoft not knowing what they are doing. I just want to stop the installation from trying to continue and remove it from my system totally. I cant even get into the standard C:\ drive windows command prompt because I cant even boot into safe mode.