Use Vista's Program Compatibility Wizard To Run Older Windows XP Applications.
For you making the switch to Vista or upgrading to Windows Vista, the need to run older Windows XP software applications is a must Have. Sometimes you will have little compatibility issues running Windows applications and programs in Windows Vista, that has been written for older versions of Windows XP/98.
If you do have problems, you can make older software applications run on Vista by setting the compatibility mode to an older version of Windows.
When an application fails to run, start the Program Compatibility Wizard by clicking on Start \ Control Panel and select 'Use an older program with this version of Windows' listed at the bottom of the side bar.

Control Panel in Classic view, you can execute the wizard, as exactly shown below, from the Run box.
"c:\windows\system32\mshta.exe" res://c:\windows\system32\acprgwiz.dll/compatmode.hta

To start the wizard, Click on Next.
In the next screen, I like to choose the first option instead of hunting around for the program executable. If you do know where the executable resides, select the third option. Click Next to continue.

After the list is display, scroll through and find the application you want to run in Compatibility mode. Pick your program on the list. Click Next to continue.

Select the version of Windows, the application was originally written to run on. If you do not know, start out with Windows XP (SP2). One advantage of using the wizard is the test mode functionality shown later in the wizard.

The next screen list options if your program has problems handling the higher quality video of Vista. For now, click Next to continue. After the wizard completes and the test fails, you will have the option to return to this screen. Experiment with the settings by starting off with disabling visual themes and desktop composition, if you can't get things working.

This table list below definitions for each setting:
- Run in 256 colors - This forces the entire screen to 256 colors while the application is running
- Run in 640×480 screen resolution — Runs the program in a smaller-sized window. Try this setting if the graphical user interface appears jagged or is rendered improperly.
- Disable visual themes - Disables themes on the program. Try this setting if you notice problems with the menus or buttons on the title bar of the program.
- Disable desktop composition - Turns off transparency and other advanced display features. Choose this setting if window movement appears erratic or you notice other display problems.
- Disable display scaling on high DPI settings - Turns off automatic resizing of programs if large-scale font size is in use. Try this setting if large-scale fonts are interfering with the appearance of the program.
Next, if the Program requires Administrative privileges, select this option. Otherwise click Next.
NOTE: You will have the option to return to this setting if the program fails to run during the test.

On the next screen, click Next to test the application. If successful select the first option and click Next to continue.
If the application failed to run or has problems (such as video), select the second option to go back and make additional changes.

After a successful test, select either Yes or No to send information to Microsoft, then click Finish to save your settings.
To reset the compatibility settings back to the original settings, run the wizard again and in the 'Select a compatibility mode for the program', select the last option to 'not apply a compatibility mode'.
One of the advantage to using Windows Compatibility Wizard, is that you can view which programs or applications are running in compatibility mode by running the wizard and checking the settings column as shown in the screen shot below.

If running an older program in comparability mode fails, check the software site updates or for more information on the program.
That's it!