I have various .NET frameworks installed on my machine (up to v4.0). I am looking to remove and re-install .NET framework 2.0, because I think it is corrupt. Does it mean I have to uninstall everything that comes after v2.0, and then finally remove v2.0, and then do the reverse (install everything back)?
Step-by-step guide: How to manually remove and then reinstall the .NET Framework 2.0
You better follow this KB guide, because it will help you to fully remove the the .NET Framework from your OS.
I'm curious as to why you think your .NET 2.0 is corrupt but to answer your question each version of the .NET framework exists in isolation so you can just uninstall .NET 2.0 and then re-install it.