Dodgy printer- help!

[dogscoff]

Hi everyone, I'm hoping to get a bit of tech advice with a wierd problem.

It's my Dad's printer. It's a xerox m750 connected by parallel port to a win98se machine. It worked fine for months, but now suddenly, it prints wierd. The first page might come out OK, but usually loads of wierd garble gets dumped into the middle of any print (text or graphic)

If I plug the printer into my winXP laptop (usb) it prints fine every time, so the problem isn't at the printer end.

I've scoured the web for people with similar problems, but I can't find any.

I've tried uninstalling and re-installing the printer. I've tried newer and older drivers. I've tried moving the printer from LPT: to USB. None of this improves the situation.

The thing is though, I'm getting a feeling that when I uninstall the driver, it isn't "properly" uninstalled. I think it kind of hangs around, messing up the above attempts to get it working. I'm pretty sure if I could purge the driver and re-install from scratch, it would work fine. (For a while anyway, but re-installing every half-year or so wouldn't be too bad.)

So myquestion is this: Is there any way I can be utterly sure that I have completely purged the driver from the system before re-installing from scratch? What files do I need to delete? What changes do I need to make to the registry or whatever?