That's a well known issue with resources that Microsoft never resolved. All that you can do is to use articles like Optimizing Windows from http://www.aumha.org/articles.htm to clean a little and run longer.
I'm a bit surprised to read such posts since a 98 user is usually quite beat up after this many years. Of course I did run into a new computer user and the PC shop had loaded their machine with Windows 98 and they were shocked at how bad Windows was...
Actually it's an over 10 year old OS (it is based on Windows 95 which was beta'd in 1994), so it's a bit of educating to share that it is what it is.
After I have surfed for a while all of my Icons turn black and soon after everything comes to a Halt??
I beleive I have sufficient Ram (512) Win 98SE 1.4 ghz