I am attempting to install RHEL 4A 64 bit on a desktop with a Nvidia Quadro NVS 290 video card. How can I get it to display in the full graphic mode (run level 5)

A good first step would be to say what problems you're having, and what errors you're getting.

A basic install should come up with a GUI, providing you TOLD it to load to run level 5, rather than 3. Changing the drivers to the 'real' nVidia stuff can happen later. If you are getting to run level 3, log in, and try typing in "init 5", or "startx", and see what happens. Otherwise, post the error(s) you're getting.

And since you're using RHEL, the first thing I'd do in your position, would be to call RedHat support, since you're paying for it.