I too suspect Vista.

But it could be a conflict with the graphics card driver file, particularly on new Vista systems. The graphics card driver updates have not yet 'caught up' with full support of OpenGL 1.5 standards. (It could take several months - or up to a year.)

Help Center topics regarding Vista: http://sketchup.google.com/support/bin/answer.py?answer=66154

You can test whether it is indeed an OpenGL problem: http://sketchup.google.com/support/bin/answer.py?answer=36252 (Try the test described under 'PC Note' at the bottom.)

This has proved successful for many Vista/SketchUp users. You should note that this is a test intended to diagnose whether OpenGL support is the problem. With 'hardware acceleration' turned off, SketchUp can run rather slowly, especially with large models, or on slower computer processors.

If this resolves your problem, keep checking for updated graphics card drivers (there may actually already be one for your graphics card.) Many new systems ship with older drivers, and the manufacturers generally recommend that you check for new drivers as soon as you receive your computer.

Regards, Taff