XP Protection Faults

I recently re-installed xp for a family friend (I know, I know, but it needs to limp along a bit longer) and we are running into Protection Faults shortly after they got it back. I suspect it's a result of them installing crap but wanted some input. If we try to print from a web browser, the browser crashes when trying to show the print dialog. Explorer throws an error when trying to see the printer's properties and I get a "you don't have privileges" when trying to apply changes in MSCONFIG. Anyone have any ideas where to look before I waste a butt load of time beating my head against it?