The first step in source code release is removal of "dumb" comments. It's probably the best to remove them, because unneccessary comments actually makes the source code a bit more harder to read and they don't give any meaningful clues to what the source code is trying to do. The "classic" example I guess is
int Get_Item(); //gets item
Things like that actually are in the source code as we speak and the reason is the long span of time the project has seen. Since then my programming skills have improved in some way.
Comments in C++ are sometimes needed, but often it's the matter of giving readable names to variables and functions after which comments are not required. So those are also things I'm probably fixing as I'm going through the source code. I have started with header files, because they are the easy ones to fix. I think header files should not need comments, with a big exception to classes, I think it's useful to comment in few words what the class is doing. The name of the class may tell it, but it's not always that clear.