Well depends on what P2 processor..if it's 350 Mhz or higher you have a chance to run Super Mario 64 and maybe other games but not with pj64.
There is another emu called 1964 which works pretty well and has a lot of speed tweaks,which is good for low-end pc's.You can also use jabo's video plugins on 1964..So try different video plugins on a low resolution and tell us how it works.
Good thing you don't have an AMD K6-2 cpu because 1964 does not work on these cpu's ( problem will be soon fixed though )
Try it..try Pj64,try 1964 ,try various roms and various video plugins.
