Why is my screen split?

Margo, try to check your settings first. Start your playstation without a disk to get into the setup menu. Adjust the settings according to your equipment

From the PlayStation 2 system main menu screen, choose the System Configuration option to change settings for numerous options including language or time display, and audio or video output method.

To use the System Configuration screen options

Turn on the PlayStation 2 system to display the main menu.

Select System Configuration and press the X button.

Select one of the following options and press the X button:

Screen Size

Select one of the following settings:

4:3 (default): Select when using a standard TV.

Full: Select when using a standard TV, when you want the largest screen possible. This option will cut off the black margins on the upper and lower portions of the screen.

16:9: Select when using a wide screen TV or standard TV with special 16:9/wide screen functionality.

Digital Out (Optical)

Set whether to output a signal through the Digital Out (optional) connector:

On (default): Select to output the signal.

Off: Select if you do not want to output the signal.

Component Video Out

Set the mode to match the input jacks on your TV when using the component AV cable (sold separately) to install the PlayStation 2 system:

Y Cb/Pb Cr/Pr (default): Select when connecting the system to component video input connectors.

RGB: Select when connecting the system to the usual Red/Blue/Green input connectors (not using a component cable). From here

Of course, also try a different monitor and see what happens. It is possible that your TV set is on autoscan which could cause this problem. But that is TV dependent, not PS2. Hope this helps, good luck.