My new widescreen Samsung monitor is a Syncmaster 226BW (connected analog).  This is my first widescreen monitor for my Windows XP system.

I installed the drivers and rebooted. 

According to the Samsung specs, the optimum resolution is 1680 x 1050.  When I try changing the screen resolution, I don't get enough choices in the settings area.  The low is 800 x 600 (of course) and the high is 1600 x 900. 

All the available resolutions are STRETCHED, most horizontally, one VERTICALLY.  So I'm not happy with any of them.

I'm stumped.  Could this be a video card issue?  The computer came out of a box several years ago -- I don't know what it's running.
What type of video card do you have?
Have you tried updating the Video Cards Drivers?

Possible causes:
Video card does not support the resolution
Generic Windows Drivers are being uses, and not the cards drivers, thus a lower possible resolution

I don't know what the card is.  Is there a way to find out without CRACKING the thing open?

Click Start > Run
type
dxdiag
press ENTER or click OK
then click the "Display" tab

Give us the information on that page, or take a screenshot and upload it at www.imageshack.us and give us a link Thanks for your help.  Here's what I've got:

That's the "System" tab.

Quote

click the "Display" tab

Have you installed the monitor driver that should be on the CDROM you got with the screen?

You should download them, then uninstall your old drivers. Then reboot and install your new drivers, then reboot again.

Probably need to set the aspect ratio. 16:10. The high resolution supported by the monitor is likely not supported by the video card.

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.