Thanks for your help, everyone.
Have you installed the monitor driver that should be on the CDROM you got with the screen?
Yes, I successfully installed the 226BW analog driver that came with the Samsung monitor.
You should download them, then uninstall your old drivers. Then reboot and install your new drivers, then reboot again.
As far as I can tell, the 226BW driver is showing up -- I can see it listed in the diagnostic and in my settings area. I did try the "update driver" option and rebooted, but my resolution options did not improve.
Probably need to set the aspect ratio. 16:10. The high resolution supported by the monitor is likely not supported by the video card.
How do I set the aspect ratio? I've looked through the properties tabs but haven't found a reference to that.
I agree with others that your onboard video may not support that monitor. But, you might try accessing your BIOS to see whether it gives you the option to increase video memory to 64MB and, if it will, see whether that makes any difference in this matter.
Forgive me, but I don't know how to access the BIOS.
I consider myself a smart guy, but I don't know anything about computer mechanics.