|If the computer is "slow", maybe it doesn't meet the requirements for Win8. You didn't list your system specs so there's no way of knowing.|
"its not full of crap yet"
No OS is "full of crap" when it's 1st installed. The "crap" comes from surfing the internet (cookies, temp internet files, history, etc), from installing/uninstalling programs, etc.
Try CCleaner & let us know if it works or not.