Hello mikesilve, welcome to Seven Forums!
If you really want the best possible space to use as storage then you need to do a wipe (secure erase
) to the entire HDD first, then create
the needed partitions and it can be done while Windows is running, have a look at the clean all
command listed in step #7 of this tutorial at the link below. Disk - Clean and Clean All with Diskpart Command
Contrary to popular belief, doing a format with Windows 7 does not remove any data at all, it just checks for sector errors and marks the space to be over-written as needed, all the data is still there including all the code from previous/failed installation attempts.