I am trying figure out what dist. would be best for me(using knoppix right now). Can anyone tell me their favorite and why?

The one you like and can get to do you what you want. You can get 500+ answers for this. You need to search out the one that fits you, no one can do that for you.

I've tried Debian, Slackware, Suse, RedHat, Fedora, Ubuntu, Vector, Blag, Sam, Mandriva, Knoppix, Agnula DeMudi, Dyne:Bolic, Studio-64, Yoper and Foresight to name some.

Personally I think Debian is the best. Stability and security, rigorous testing and it doesn't seek to make decisions for you.

That said, most of the distros I've listed have their advantages.
Strip away the logos and splash screens and you have Linux whichever distro you pick.
There probably isn't "a best" distro, just keep trying different ones until you find the one that you're happiest with.

If you are used to Knoppix why not just use that. You could also try a few others if you have free space on your computer and pick the one that works best for you.