Hi,
The first question is whether your motherboard supports the 2.0 standard. IF your pavilion is older than mid 2002 or so then it doesn't. But you can get a pci card that will add that capability - and you should make sure that that card has drivers for Win98se. Most probably do.
The same will be true for firewire and Win98se.
Something along these lines would work for you:
http://www.newegg.com/app/ViewProduc...111-602&depa=0
Daf