What monitor do you have?
Make sure that the monitor driver
for your monitor (as well as the graphics driver) is installed.
You can check what monitor driver is installed, and change the monitor driver, by going to Control Panel
tab > Device Manager
...Right click the monitor and click Properties
to find out what monitor driver has been installed.
The monitor driver provides information to the system about what resolutions, color depths and refresh rates the monitor supports. It's usually obtainable from the manufacturer's website of the monitor. Since 1440 x 900 isn't a standard resolution, you won't be able to use any of the generic monitor drivers provided with Windows XP.