How can I safely remove Ubuntu 10.10 from my PC / or How do I access Ubuntu files from inside Windows 7?

I’m used Ubuntu a couple of times, but it’s not my distro of choice so some of this may be a bit off. I had thought Ubuntu already had what it needed to read from a Windows partition (these days, it’s Fuse) and automatically mounted it. Try looking in the /mnt directory for a Windows folder. If there isn’t one, look up the mnt command, figure out which is your Windows partition, and try mounting it yourself and see if it works.

Grub might need to be uninstalled before you remove Ubuntu, if you go that route. But I’m not sure if it replaces the MBR when it’s uninstalled. If you have the media for Windows it should be possible to boot from the CD in Recovery mode, I think it’s called, and re-write the MBR from there.

This may be of use:

http://www.howtoforge.com/access-linux-partitions-from-windows

But if that doesn’t work, this method should work.

First, place a Live CD of Ubuntu in to your computer and boot from it. Choose test, or whatever mode lets you use it from the CD. It should be able to access both hard drives, so copy the files from your ubuntu partition on to your windows 7 partition. I know that’s not exactly what you asked, but that will get the job done. After doing this, go to the partition manager and delete the ubuntu one, and expand the windows one. Lastly, eject the CD and reboot. If it gets angry, you may need to go in the bios and adjust the boot order so it boots from your windows partition.

Windows cannot read foreign file systems (like ext4, the one Ubuntu uses by default) by itself, but there are programs out there which you can install to get this functionality.
If you have deleted the Ubuntu partition, then you most likely won’t be able to access the files that were there then, but if you can find a program that will give you ext4 support (the ones in hungerforpizza’s link appear only to support ext2 and ext3, although I just read that ext2read supports ext4) then you will be able to read the ones currently there.

Out of curiosity, did you ever see a GRUB menu on your previous install? It sounds like GRUB was attempting to boot into the default OS (Ubuntu) without the normal user delay (mine is set for 3 seconds, enough for me to press a key before it jumps into the first on the list) and therefore choked when it couldn’t find the UUID of the target partition (which had been deleted). Anyway, I’m glad to hear that problem is solved. Good luck.

As for properly removing Ubuntu: you have removed Ubuntu, but not the program (called GRUB) that is on your first hard drive (the one with Windows) that tells the computer to start Ubuntu. So now when you start your computer, that program will try to start Ubuntu, which is no longer there, causing the error you posted. This Google search should turn up some results that can help you.
(Note: after you’ve deleted your Ubuntu partition, you’ll probably also want to create a new clean partition in the now free space so you have more room for your files in Windows.)

As you accessing your Ubuntu files from within Windows: for that you’ll need to install a program in Windows that allows you to read ext4 filesystems, which is what Ubuntu uses (as opposed to Windows’ NTFS, if you’re interested) and isn’t supported by Windows by default. You should be able to use this search, it looks like ext2read should be able to do what you want.

Just as a side note, you can remove GRUB using a Windows XP install CD. Just pop the CD in and boot to the recovery console. I don’t remember the exact sequence of moves to make from there – just look for the way to restore the master boot record. That should work.