I want to know if there's any way to delete game progress such as 

Complete the game on Normal difficulty unlocked Hard difficulty plus all these extra features.

I want to know if its possible to start all over from before even completing the game the first time. By deleting all game information.

Imagebreaker : You can go in and delete your save files if for some reason that is what you want to do.

Save files are stored locally on your PC in the Vizzed directory. Depending on your Operating System: Computer/C:/Program Data/Vizzed/Vizzed RgrPlugin/

Try going to Start Menu > All Programs > Vizzed Retro Game Room > Open Plugin Data Folder > User-216567. In that folder you'd find the different game system folders since save files are saved locally on your PC instead of Vizzed's server.

So, the save files would be the following:

Save File Types
.sav = Game Boy Advance & Game Boy Color & Game Boy - Save File
.sgm = Game Boy Advance & Game Boy Color & Game Boy - Save State File
.sav0 = Nintendo 64 - Save File
.eep = Nintendo 64 - Save File
.m0-.m3 = Nintendo 64 - Save File
.sav0 = Nintendo 64 - Save File
.srm = Super Nintendo - Save File
.zst = Super Nintendo - Save State File
.zs1-sz9 & .z10-z99 = Super Nintendo - Save State File
.fc0-.fc4 = Nintendo - Save State File
.gs0 = Sega Genesis & 32X - Save State File

Etc.

Also this should be in Retro Game Room forum so I'm moving it there.

If for some reason you can't access the Data Folder, or the directory Jordan gave, you might find it in your Local Settings folder.

Imagebreaker : Please let us know if you need further assistance figuring this out.