I didn't mess it up installing, I messed it up deleting. I had installed Linux fine, but I was having problems installing Nvidia drivers, and it made Linux not want to work correctly (some x server bullstuff, could only use Linux from the terminal). After like an hour of loving around trying to fix it, I decided to just remove Linux and reinstall it fresh.
This is where the problem came from. I had a dual boot with Linux and Windows 7 using Grub, but rather than uninstall Linux correctly, I foolishly did it by erasing the Linux partition from within Windows, not realizing it would make Windows unbootable.
So to remedy this, I booted into the Linux Mint live CD, and tried restoring MBR from there. To do this, I tried installing Syslinux. I had to install it from the Linux terminal, and I made the mistake of trying to install it to /dev/sda2/ (my Windows 7 partition) instead of /dev/sda/ (the whole hard drive). This overwrote some critical component of my Windows install, rather than rewrite the boot files.
I thought this had wrecked my Windows install, because that partition wasn't even visible inside Linux. So I reinstalled Linux proper, with the idea that I would have to use it as my main OS for the time being, and that my Windows 7 partition was completely ruined and all my data lost.
I used Linux for a few hours, trying to get used to it. On a whim, I decided to try making a Windows recovery disk, to see if maybe I could fix Windows, but not expecting to. So I burned the disc, booted it, used bootec /fixmbr, blah blah blah. Long story short, I'm back on my fixed Windows 7, and I completely got rid of Linux mint, except correctly this time.
The end.
