Pentium 2 overclocking

Well, depending on the options your Bios gives you, you can start playing around with the FSB values and the voltages (be careful though, those CPUs don't have any kind of protection and will fry if temps get too high).

If your BIOS gives no such options, you'll have to do some research into pin modding.

any idea where I might find information on pin modding? did i mention they are in cartridges in slots?

Its probably the Slot 1 mounted "Klamath" P2, and should have unlocked multiplier. Overclocking through multiplier is safer on old systems as raising FSB will in most cases raise PCI and AGP bus frequencies too, which may result in damage to components other than CPU. If your motherboards BIOS doesnt offer any cpu options then the motherboard might have a set of jumpers for FSB and multiplier settings(well, it pretty much should have one or the other). Do you know what motherboard is it? Inspect it thorougly first, because pin mod on that cpu(if possible at all) wont be no simple pencil mod but will most likely involve soldering resistors onto cpus pcb.

And for comparison - I once installed XP on an old laptop with 400mhz cpu and 128mb ram - it ran horribly slow

well, i haven't looked on the motherboard for pins, soldering, i can do if it comes to that, and they are gonna be test computers for me and a few friends of mine, i dont care if its slow, i just want it to run xp so we can use them, they will run 2000 but not xp. what is a klamath?

Klamath is a code name for the cpu core, just like todays Wolfdale, Penryn etc.