Windows Photo Gallery connects seamlessly with Windows' own Screen Saver application (except for the one small quirk about the descriptive tags) and you should be able to create your own customized screen saver in only a few minutes. We have a lot of great reviews of security software, but it would still be better not to push your luck. If you like screensavers and don't want to spend money buying a commercial one, and don't want to put your system at risk with a 'screensaver' that's nothing but a delivery system for malware, creating your own is the way to go. If this happens, you can check this article for a solution: 'This Computer's Video Card Can't Play Themes' Message in WLPG Screensaver Settings Dialog.
NOTE: If you have a really old and/or really marginal video card you might get a message saying that your video card can't play themes.