pphys files?

in 2.49b blender makes folders with pphys files.
what are they for?

They’re the files that contains the physics (i.e.: softbody, cloth) data from each frame you baked it for.

cloth i use - but i don’t bake anything.

Even if you don’t bake blender stores the result of physics simulation.
Internal that is called physics cache.
Cloth and soft body calculation can get very CPU consuming with complex meshes and collision,
such that a frame may take minutes.
Once your animation is completely cached it can play “real time”.