7 options in grub menu

I have done a side by side install with Windows 7 prof 64 bit (was already installed) and BT5 (just installed a few days ago). I'm not having a problem getting into either of them, but when I start my computer and get the options to choose which OS to load I get 7 choices!

1) Ubuntu, with Linux 2.6.39.4
2) same as above (recovery mode)
3) memory test (memtest86+)
4) memory test (memtest86+ serial console 115200)
5) windows 7 (loader) (on /dev/sda1)
6) windows 7 (loader) (on /dev/sda2)
7) windows vista (loader) (on /dev/sda3)

I understand that the first choice is BT5; and the second choice makes since as well. not sure I know the difference between choices 3 and 4 but I'm not really worried about those. My question is why I have 2 windows 7 loaders and a vista loader. this is my first time with a multi-boot set up so I am just wondering if what I'm getting is normal?

The reason I'm curious is because I can log into either of the windows 7 loader choices and everything seems fine either way, so I'm just wondering why I have 2.

beyond this little issue, I am enjoying myself so far, it has been so long since I have worked outside of "Windows" environment, and have forgotten what it's like to actually have control over my PC! I have a lot to learn about Linux, and even more to learn about BT. thanks to any and all who answer

Those should seem pretty relevant but, 3, and 4, are for memory (RAM) testing purposes. 5, 6, and 7 are the windows partitions, that are setup on your machine,
I would guess that one of the three is the actual boot partition, one is a backup partition, and the third one, is the actual OS itself. While number 7 seems a bit off in the name, (unless you have vista installed as well) but it is probably just a mistake that grub made when it tried to determine what is on the partitions and give them names.
You could correct/change them if you wanted to, ( if I were you, I would leave them alone) but if everything is working fine there really is no need to.
Further if you don't want to see options 3 or 4 you could remove them. Again there really is no benefit other than perhaps saving some screen space. But even that is silly compared to messing around with the grub config, and ruining something.

yeah everything seems to work fine, and from what I understand all windows 7 installs have a vista loader as well. my Only real curiosity was with the 2 windows loaders. What's weird is that either one of the 2 windows 7 loaders seems to work the same as the other. i get the same login options, it all appears to be the exact same; cept there are 2 ways to get there... just seems a little odd, but then... it is Windows.