Timmiski; This thread is really, really old. However, Windows 7 is still my favorite MS OS. Back a few years ago I played around with different ways of adding partitions. Here are some of the options:
Burn the Install media to disc and delete the partition.
Install windows 7, but use the install utilities and only create one "Primary" partition. The contents of the 100 MB partition will be put in the same partition with Windows 7 defeating the extra security the separate 100 MB partition provides.
You can use a second hard drive to create 4 additional "Primary" partitions for your use. Works well for a tower case computer with space for adding hard drives. Not so much for laptops or micro case computers that do not allow adding hard drives.
You can create your last partition as an "Extended Partition" and add as many OS as there are letters in the alphabet. If you keep the 100MB "Primary Partition" you can use the Windows 7 boot manager to boot to all of the OS in the "Extended Partition."

Finally, you can use the "Virtual Install" to install OSs like programs and run them inside Windows 7.
Hopefully, you now have some more googling to do ... ?
;})