Doesn't really matter. A reinstall is rarely a problem since it uses the same hardware signature stored in MS Activation servers for your Product Key.
Always boot the installer for installs, so you can use Custom install Drive Options to delete, repartition, and/or format the target partition, or not.
Here are tips for getting a perfect reinstall of Windows 7 based on thousands helped with here: Reinstalling Windows 7
Once you get the perfect reinstall, save a backup image as shown so you never have to reinstall again - just reimage the HD in 20 minutes from stored image, the modern way!