Hi,
WIn98 ??? No, No, No.
So we left with 2 options.
Well, WindowsXP Pro ( not Home Edition ) got a support of a width range of DV devices but still got a little compateble problems with some editing software, the premier works just fine on XP.
Windows2000 Pro, support a lot of editing software but less Dv hardware devices.
Both systems are very stable which makes them very suitable for that kind of work.
Buttom line, if you got enogth time install XP and see if you got everything working on it and if so stay with it.
If it gives you problem install from scratch WIn2k.