Windows 7 SP1

So I have decided to upgrade to Windows 10 from Windows 7. Now if for some reason, I decide to revert back the changes, meaning roll back everything to the way it was before (including the OS and all files), is there any way that can be done? (I haven't installed Windows 10 yet)

Hello I currently use these Steelseries v2 headphones and it generally performs fine although I can barely hear myself so I sometimes get too loud and everyone in my house can at times easily hear me. I know that there's the playback volume thing in the Realtek audio manager but its rather quiet...