hey, what is the latest version of slackware? Also, which is the best out of:

Red Hat
Novell openSuSE
Slackware
Linspire
Ubuntu/Kubuntu/Edubuntu/Xubuntu
Xandros

If you'd bothered to read the Slackware website, you'd see that 12.0 is the latest version :/. Clearly, Slackware is better than those other distros . Seriously, there's not really a "best", but a "best for you", which only you can decide.

I just want a cool looking, powerful linux OS.

Well looking cool or not will depend on your desktop environment. Kde looks the same from one distro to the next. Same for gnome etc. It comes down to how much you customise it.

Powerful? Well that will likely come down to your choice of kernel and applications. Learn to compile your own kernel and that will help. Get the latest source from kernel.org and check out the sticky at the top of this forum.

Basically the nature of linux is that it comes down to you to make it as powerful as you want it to be. That's my opinion anyway.

You will find that slackware does things a little different to most distros. Most configuration is done by editing text files. Learning to use a console text editor like vim or emacs is a big help. It has the reputation of being 'clean' and 'stable' because of this, and fast too. You will be learning what goes on under the hood with slackware. A lot of distros hide this from you with gui configuration tools.

My best advice is try a few distros out and see what suits your needs.

What will you be using that power for?

You can always try out a few LiveCDs to get a feel for other distros.