It may be worth a look at the manufacturers websites for the definite system requirements as I too am running 98 1st ed. Some 'shopping sites' show different info from the ACTUAL specs needed. For example. The Creative Jukebox only needs 1st ed but sites such as Amazon and Kelkoo show it needing 98SE. Also, my digital camera said it needed SE so I waited for the error messages to pop up during install but it runs fine.
Sorry All3 I have just got back to the computer. All I did to install 98se over the top of 98 was to click start>Run and typed in D:\setup.exe and the CD did the rest. All it doe's is overwrite some of the 98 Files and add's some new one's.