I have used Unix before but I am new to SLES and I need to run a gui based installer on a new AWS image of SUSE 11.3.

I wanted to remove Putty/SSH complications from the equation so for now, to check if XWindows is working I directly connected to the SLES desktop using xRDP as ec2-user, and from xterm I issued the following commands:
su - root
export TERM=xterm
export DISPLAY=localhost:0.0

After checking the variables, I launched xclock but it fails making me conclude that Xwindows is not correctly configured or running.

Can anyone point me towards a step by step guide on how to setup XWindows, or given my dated knowledge, is there a better way to run a gui-based program?