Hi Roger, welcome to BC.
Crashes in 3D screensavers, more often then not, points to a video driver or DirectX issue.
Provided you are using the factory integrated graphics system that came with your Dell, go here,
download and re-install the video drivers for it. You may want to print the installation instructions as the procedure is a bit different from the norm.
If it still crashes on you, go here,
download and install the DirectX 9.0c redistributable package. That version is normally included with XP SP2 but may be corrupt.
Let us know.