I have to say this:
I used Win98SE for a long long time. I loved it. It was better than 95, WAY better than ME, but when XP came out, and I made the switch -- I wasn't going back. With 98 when the system crashed, it crashed. It stayed there. You have to hard boot because you couldn't even shut down (no explorer listed in the task manager).
With XP, it catches 90% of all crashes before they happen, it doesn't crash. On the odd occasion that it DOES crash, it restarts explorer in the task manager and you may continue from there.
In all the many years using Win98SE I rarely got a BSD, and when I did it was my fault (installing/running questionable drivers, bad software, etc). I don't think I've ever gotten a BSD in XP, ever, since I've been using it.
Keep in mind I'm using XP Pro, a retail copy (not a pre-packaged "BloatWare (TM)").
XP was way way more stable than 98SE in general. I had to go through more hoops to set XP up the way I like, but its possible. Also, now that I have upgraded and have a lot more RAM (from my 98SE days) I'm glad I've got XP. 98SE doesn't handle large amounts of RAM so well. XP does (up to a limit).
So there's no benefit to running 98SE if you have XP. XP is better in several categories, including stability and memory. The ONLY reason to run 98SE is games. To me that's not a valid reason to choose your version of Windows.
As with all the other comments about 98/XP, mine are subjective, but I have a lot of first hand experience with both OSes, and XP is better in my book.