I purchased a wider screen and all my photos look stretched or squat. How can I return them to normal.

The properties dialogue box is only showing Internet Explorer Microsoft Answers, so I cannot click the Settings tab.

It sounds like you opened a different dialogue box.

Right-click the desktop (your background picture), and then click Properties. The window that comes up should have a Settings tab you can use to change the resolution using the instructions above.

Have you tried changing the resolution in Windows XP to the native resolution of the monitor?

To change your monitor’s resolution

1. Right-click the desktop, and then click Properties.
2. In the Display Properties dialog box, click the Settings tab.
3. Move the Screen resolution slider to the left to decrease the resolution of your monitor, making text and pictures appear larger. Or move the Screen resolution slider to the right to increase your monitor’s resolution, making text and pictures appear smaller.
4. Click Apply to have the new resolution take effect.
5. If the Monitor Settings dialog box appears, look at your display. If you like the new resolution, click Yes. If you do not like the resolution, click No, and return to step 3 to try a different resolution.
6. Click OK.

http://windows.microsoft.com/en-US/windows-xp/help/setup/change-monitor-resolution

Have you tried changing the resolution in Windows XP to the native resolution of the monitor?

To change your monitor’s resolution

1. Right-click the desktop, and then click Properties.
2. In the Display Properties dialog box, click the Settings tab.
3. Move the Screen resolution slider to the left to decrease the resolution of your monitor, making text and pictures appear larger. Or move the Screen resolution slider to the right to increase your monitor’s resolution, making text and pictures appear smaller.
4. Click Apply to have the new resolution take effect.
5. If the Monitor Settings dialog box appears, look at your display. If you like the new resolution, click Yes. If you do not like the resolution, click No, and return to step 3 to try a different resolution.
6. Click OK.

http://windows.microsoft.com/en-US/windows-xp/help/setup/change-monitor-resolution

The properties dialogue box is only showing Internet Explorer Microsoft Answers, so I cannot click the Settings tab.

No, it came on its own and I just hooked it up to what I had.

Did you wide screen come with any software such as drivers?

Did you wide screen come with a manual so that you could read about changing the resolution etc to suit the wide screen?