Number6 has the right answer for this, but if you really want to get rid of TouchWiz over the long run then you should consider buying an Android phone without it. Check out some of Google's Nexus phones available on Amazon:
Someone just asked this question yesterday. My answer from that question:
"You can’t really uninstall it. If you are rooted, you can install a new ROM of Android that doesn’t have TouchWiz, but that’s not an option everyone wants to explore. Otherwise, the best you can do is go through your settings and disable as many features as you can. You can also install a custom launcher to change the appearance and get away from the TouchWiz launcher, but that won’t really uninstall it.