Thanks, but not quite what I was going for. I know how to change the filename. What I would like to know is how to change the Title so it matches the filename in Windows Media Player. I change the filename but the title remains as before so the files are still listed in WMP by their original title.

Here's a screenshot of what I'm trying to get at. I've set WMP to view by details rather than icon to get the pictured display. On the left circled in blue is the media title, which was originally the filename as it came off the camera. On the right circled in red is the new filename that I've given the file using Windows Explorer. So you can see that the file name is now rocket.mp4 while the title is M4H01706. This becomes a problem when the media player I'm using only displays the title and not the filename.
What I would like to know is how to change the title so it matches the filename. I know I can go into WMP and edit each one manually but it seems a waste to have to change both the filename and the title manually. I would like to know if there is some way for the title to update automatically to match the new file name.
Hopefully I'm clear in what I'm after.
Thanks.
All of that information is encoded into the file metadata. If you were changing an entire category (like genre say) in WMP to be the same for multiple files you could select all of the files within that column, pick edit and all the selected files would show the new genre, or whatever.
I think what you might want is a 3rd party app something along the lines of this:http://www.zunescene.mobi/forums/index.php?topic=8887.0
But I don't yet know of an other similar app that handles miscellaneous video file types.