Change Folder Ownership and Permissions

I have a lot (about 3000-4000) of user home folders that need to have Ownership and Permissions changed so that the user is the owner and then has explicitly defined Modify permissions. These changes will need to be recursive through the sub-folders as well. One good thing is that the folder name is the same as the user name.

OS is Windows 2003 Std.

Here is an example:

Folder name: User123
User name: User123

Any help is greatly appreciated.