Windows 8 PC Reset. Taking toooo long.

Now I understand this will take a long time but I did NOT plan for it to take this long. When I upgraded Windows 7 to Windows 8 the format and upgrade only took 15 minutes. I was having some pc issues and said Hey! How about I use this new reset feature and start over again. WORST MISTAKE EVER! I have no clue what this is doing but this is taking forever. So far this thing moves up 6% every hour. It's been 3 hours now and it's still on 16% Can you all tell me what is this thing doing or is this some sort of error? My hard-drive size is 1TB clean and around 900gb when a OS is installed.