After installing 98SE from a original disc or upgrading through a 98 -> 98SE upgrade disc, your computer should be busy for at least 20 minutes if you have broadband and are using the automated Windows Update.
If not, something is wrong.
Also, when you're finished updating, validate it through their 'original software validation service'. It makes the overal updating next time you visit W. Update a lot smoother.
All in all, I'm running a now fully up to date original copy of 98SE on a PIII 450 with 256 MB and it runs very smooth.
Be sure to get the lastest ODBC drivers too.
The latest version is 3.525.
Good luck,
M.