Aye, as zabeal and Nilrem suggested, this is a resolution problem. Basically, if you have a lower desktop resolution selected than the ingame resolution, this effect will occur.
The solution is simple: either set your desktop to the same resolution as PS or higher, or reduce the PS resolution to the desktop resolution or lower using the configuration utility that is included with the client. Look at the PS program group for this and the updater, and search the boards on how to get the updater working if it doesn\'t work out of the box.
Don\'t use the updater until the server is back up, though.
You can also use PS in fullscreen mode (via pssetup) if you don\'t want to change resolutions, but be aware that there is a crashing problem when you switch away from the client in fullscreen mode.