Is it possible to return everything to default, I mean settings, remove skin downloads without using up a install, a factory reset is what I'm after.

EDIT: or would it be better to do clean install and then copy all the folders, then when I want to reset everything copy them back?

Backup your data/misc folder as this contains the unlock data.
Uninstall, reinstall, copy misc folder back.

That works a treat, thx.