Ubuntu :: Can't Remove Containing System32 And Flash, But Nothing Else)?

I'm using Windows 7 as my primary operating system. I've been searching but have yet to solve my problem. I suspect my lack of knowledge regarding operating systems is partly to blame. After a long and difficult process of installing Ubuntu (not Ubuntu's fault), I finally got it to work as an application within Windows via burning the .iso onto a CD. I had some difficulties that I suspect are related to a previous upgrade from XP to Win 7 and the fact that I have two hard-drives.

Anyway, I go into my computer and if I wait it automatically selects windows 7. However, my options look like this:

Earlier version of windows
Windows 7
Ubuntu
Ubuntu
Ubuntu

The first two installations do not work. One does not even load, if I recall correctly. The third appears to be properly installed as a partition within the same drive as Windows 7 (I previously intended to install it on the other drive, which has a windows file I can't remove containing System32 and flash, but nothing else).

Anyway, there are other problems going on, but my primary concern is just cleaning things up to remove the two additional Ubuntu options. I've looked around for previous installation files (though I had been uninstalling them before) and I've been unsuccessful in terms of removing them.

My third instance of Ubuntu is working well and it seems like a nice operating system so far. The CD is no longer needed and is not present in the drive. Sorry if I was unclear. As I mentioned, I'm fairly unfamiliar with operating systems. This is my first time dealing with them (I'm learning programming languages and Linux seems like a better OS for some of them - Ruby, in particular, which seems to have differing code for different OS')