pretty sure the answer is no. XP programs are not 98 programs. I've never actually TRIED to do this, but its probably not possible.
What IS possible is you search around on the internet for a slideshow screensaver for win98. Just make sure its freeware (unless you want to pay for it or look at nag screens) and that it doesn't have any spyware, adware, etc.
**five seconds of google searching finds you this:
http://www.dcatsoftware.com/mswind/dss/main.htm