You can use "Aglare 3GP to AVI Converter" software to convert your video 3gp files into avi format.
Aglare 3GP to AVI Converter is powerful 3GP converter software for all mobile phone users. The 3GP converter allows users to convert 3GP to popular video file formats such as 3GP to AVI, 3GP to MP4. All conversion processes of Aglare 3GP to AVI Converter are very fast and easy to handle.