The free AVS Video Converter can also change the file into any sort of editing program friendly file type like AVI, although you will lose quality; so only do as a last resort. http://www.avs4you.com/AVS-Video-Converter.aspx
In regards to what Skorch mentioned, VirtualDub does not
work with the Hauppague. Vdub can only edit AVI, and the Hauppague compresses its data as it captures which is in the M2TS and Mp4 and all that business. It will appear to work, and Vdub will record it, but it can not be played back or edited due to this feature. So it would be best to convert into a file (like AVI) that Vdub can edit, and just capture using the included software. (Info from Doom9's forum).
I have heard vague stories of being able to record with Windows Media player, but I have also heard that Windows does not recognize the Hauppague.
Also, AVIdemux, an open source editor made for Linux (but it does have windows and mac versions available), can edit MP4's and M2TS.