tiger is right on the first part of going to ndis wrapper is only for wireless cards and not for video drivers. if you cant fix your res problem under that menu then your X11/xorg.conf file needs to be reworked. also try checking under hardware drivers for a different version of the video card driver. I myself am a ubuntu user and i also noticed that on the switch from 8.10 to 9.04 there are a lot of vid cards that have been blacklisted so you may also wanna chech that out also. good luck

Did you install the propriatary Nvidia drivers in System – Admin – Hardware?
If not thats your problem. I had a similar issue and this solved it, and I was able to adjust the display under System – Admin – Nvidia.
If this isn’t it this, perhaps you can get the windows version of the driver and install it onto your system under ndiswrapper, I fixed my netgear wireless G USB dongle by using ndiswrapper.
Nvidia doesn’t have a whole lot of support on Ubuntu, so I think thats the main problem, the only drivers are Nvidia proprietary…
Good luck and kudos for using Ubuntu 9.04 linux…its a top notch OS and I’m in love with my version.