Type Opera:Config in the address bar. Go to the user preferences section. Change your user agent string to that of a desktop browser. A standard Internet Explorer 6/Windows XP UA string looks something like:
Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1)
[Edit: Also, depending on what build of Opera you are running, you may need to change the following line in the opera.ini file:
UAProf URL Enabled=1 -->Change value to 0]
