I own a Mac Pro and it came with 10.4.6 installed. Once I booted up OSX asked to upgrade to 10.4.7 which I did... This has now broken a bit of kit I need. I need to revert back to 10.4.6 - is this possible?
If you haven't done this yet, use the install discs, and do Archive and Install with carry-over of existing programs and settings (that's not exactly what it's called, but you'll figure it out). To do this, follow the disc prompts until you get an Option button (should be lower left of the main install window). Then click it and you will get some install options, one of which is to do this.
This way you will not have to re-install any of your kit, and the whole thing really should take 15 minutes.