Not helpful ^^ Try & get the free trial of 3GP VIdeo COnverter thats what I use to convert through MP4 to AVI,DIVX,MPEG & others
best video converter i know is " Xilisoft Video Converter " a lot of different types of videos u can convert with this (.mp4 , .3gp of course too )
Thats the one i Posted but forgot the Xilisoft Its the best I think atm coz converts the required formats you need