I have no idea how to make the lineart that I draw smoother and more pronounced on the computer. Help?

I want to backup my windows 7 registry, so as to restore it when there is something wrong with my computer.
Help!!!!!!!

It says it will remove unneccesary, files, registry entries and internet clutter from my system to free up disk space.
Will this take away all of my folders and pictures and stories and poems I’ve written and stuff that I have on my desktop? Is this a good thing to do or is almost like rebooting a computer?! HELP!