New pc buying advice

Hi

looking to buy a new pc and like input

last pc = 2.8hz \ 1g duo \ 120G HD

I’d prefer Xp but most seem to be Vista cross fingers to form a cross
PC not Mac.
I fancy laptops as they are easier to move.

to future proof what should my spec be? I don’t game too much, so I guess I could go middle of the road.