I have openSUSE 11.1 (KDE4) installed above old openSUSE 10.2 installation, so that my old accounts survived and working.
The only one problem I have with Display resolution. In root account it is 1920x1200 (as my monitor supports) but when I login into user account I get only 1280x1024. I can then manually change it to 1920x1200, but on next login it again appears 1280x1024. Apparently this resolution sits in one of my old configuration files.
Take a look in Systemsettings-Display. Your resolution should be available there. Change it, apply, Save configuration and you should be done. On the fly.