No offense, but don't you guys ever learn about torrents.
The 100 MB partition is built by Windows 7 install and that's where it boots from.
This happens when you upgrade rather than choosing a "clean" install. A "clean" install is the only way to go. You end up with hundreds of useless files on your system and conflicts can also arise with drivers/
Even before attempting this you should download a free utility to manage and./or fix the Boot manager. It's called EasyBCD and can be downloaded here: EasyBCD 1.7.2
truthfully, I would reformat everything and start over with a clean install.
This will also eliminate the 100MB partition.