Clean All command will zero the drive which takes a long time on a large HD but is the deepest clean.
Very likely that boot partition is blocking your install so good to get it cleaned off since you want your HD cleaned.
Then boot DVD, select Custom install, use Drive Tools to create New partition(s) as you wish, format before installing to first partition.
Intsaller is driver complete with newer arriving quickly via optional Windows updates. Put your wireless driver on a stick in case needed to get online. After updates, find any drivers missing in Device Manager plus any favorite apps on the Support Downloads webpage for your model computer/device.