I used these instructions from the folks at AVC to convert the video to a more friendly WMV3 codec:
http://www.any-video-converter.com/convert-g2m3-g2m4-codec-video-to-wmv-avi-mp4-flv.php
Step One:
Please click here to download and install the gotomeeting codec.
Step Two:
Please go to C:\Program Files\Citrix\GoToMeeting\723 (a folder with numbers, which is the version of GTM you have installed). There will be a file called "g2mtranscoder.exe". This is the utility that GoToMeeting uses to convert the file to a generic WMV file after recording.
Step Three:
Now follow the instructions below to use command line to convert the WMV G2M3/G2M4 Codec Video file:
1. Copy g2mtranscoder.exe AND g2m.dll files and paste them onto the ROOT C: drive (ie not in a folder).
2. Place the GoToMeeting recorded WMV G2M3/G2M4 Codec Video file on the ROOT C: drive as well.
3. Launch the command prompt (start -> run -> cmd).
4. If the command prompt launches and shows a file/folder path (ie C:\Documents and Setting\etc) then type "cd.." (without the quotes) until you are seeing just the root C: in the command prompt line (will look like C:\>).
5. Now, type the following at the prompt: "c:\g2mtranscoder.exe source=c:\videofilenamehere.wmv". (Of course put the name of your video file instead of those words and don't forget the .wmv).
7. When the g2mtranscoder.exe process stops, you would get the WMV WMV3 codec video in ROOT C: drive, which has replaced the source WMV G2M3/G2M4 codec video.