UT2k3 Problem

[Flashingfish]

Ok - I have a problem while playing UT2k3: every couple of minutes everything freezes, just stops dead for a few seconds, and then carries on as if everything was normal. It's very annoying

Because I trust in my PC I put all the graphical settings to the maximum straight away, but I encountered this problem. So I put everything to the lowest settings possible. that's 320x240 res (thereabouts), 16 bit colour, no details at all/lowest details. But I still had exactly the same problem. I also tried stopping all my usual backgrounds problems, but this didn't help. And btw this is all offline gaming.

There aren't any error messages at all, just a pause ;x

So.... I use:

Windows XP Professional (5.1 Build 2600) (no updates because I refuse to)
It's UT2k3 out of the box which I got for christmas =]
AMD Athlon Xp 1800+ processor
I'm not sure about the motherboard... I could look if it's important
256mb DDR (pc2100?) ram
Not sure about the HD - don't think that's the problem
I don't think the CD drive is the problem....
Inno3D GeForce 4 ti4200 with 128mb DDR ram
It's directx version 8.1 (4.08.01.0810)

I'll upload my dxdiag in a few minutes...if that helps

Thanks anyone who can figure this out =D