Vikenk,,
I know the laptop that you are referring to and although it is rated as a PII/400 , it is a laptop,, not a desktop and for some reason,, the 600 series TP do not perform well,, i mostly deal with the 600x models,,,
In your situation,, I agree with your last post to go Win2K pro,, with 256 MB of Ram,, that should give you the performance and stability that you will be content with,,
If you do go to XP ,, i would suggest that with that model you move to 512 mb of ram,, that should provide the little extra "OOmph!~" that you will require on the model,,
With Xp on it,, with 512 your performance and stability would be good,, but you will still have some slow pages/apps,, due to the architecture in the TP,,,
with Win2K,, your performance will be "good" with the 256mb and you will have a scaled down "look" of XP when you take the Glam off of XP,, but you will have the stability of the NT OS,,
Win2K... Best Bet, Best Satisfaction at no cost,,
cheers