Using CD to repair OS

Is it possible to use a disk that did not come with your computer to repair your computer? Here is the situation. I need to repair a Dell Dimension 2400 that has XP home on it. I have a disk that came with a Dell Dimension 3800 that has XP home edition on it. Again, I just want to do a repair, not an install. Will this work?
you can use a home edition to repair, but if the pc is at sp3 then the repair cd has to be at the same service pack. If you can get a cd it would be better to save your data to a flash drive and reinstall rather than repair.
OR, you can slipstream sp3 into your installation cd, there are several ways to do this, I have my cd with sp3 slipstreamed in.