Nomi1985

I already had Windows XP installed on my C: drive. I bought a new hard drive and then installed Vista on it (Drive D:). I started the Vista install from inside of Windows XP, so it dual booted the two systems. Now whenever I restart the computer, it asks me if I want to start "Windows Vista" or the "Earlier Version of Windows". I want to remove my C: drive from my system and only run Vista, which is on the D: Drive. Whenever I do this, however, I get a message saying that NTLDR is missing and I can't boot into Vista. How do I fix this problem so that I can finally get rid of Windows XP? I would really appreciate any help with this matter. I've Googled the hell out of this problem and tried a lot of different things all to no avail.