It looks right to me. Just the System Active MBR partition with possibly some extra files (
drivers?).
Unhide System and Hidden files in Control Panel>Folder Options>view tab to see if anything else is in there.
You're right, however, about the problem with a drive letter enabling Backup or other files to write there. We see this problem a lot here.
We can of course help you remove it to recover it's space and System active MBR into Windows 7.
However with all the space you have there, I'd just follow SIW2's commands above to remove the drive letter.