When you are working in Windows, one of the famous sayings that is to be remembered is: "If it aint broke, dont fix it". Unless you are facing problems due to the .NET framework, why not just let it be? Also, remember that a framework not needed by any tools in your PC now may still be needed for some software that you may download in the future...
If you still insist on removing, and are not sure what dependencies are present from other software, you can consider removing all of them and then, if a program gives issues with running due to missing framework, you can re-install/repair the program to get the particular framework back...
Arun