Mobile format question
 

Hello everyone. I have been searching around the net and getting mixed answers. I have several hundred videos to convert for my cell phone and my question is, which is the better format. 3GP or 3G2?

Some sites say they are the same, some say one is better than the other. My options are:

1. 3GP rel 4
2. 3GP rel 5
3. 3GP rel A
4. 3G2

Any help would be appreciated as I know nothing about these formats. I have been tweaking the settings on all of them and so far I cannot see any difference unless the bit rates are higher, etc..

Pretty much what I need to know is which one has the best quality and which format is used more on most cell phones.