Video file advice request

I've got quite a lot of these, they avi files of family and events. It would be quite good to have some on my smart phone, but the file sizes are too big. I'm sure they should be converted, but to what and how do you keep the quality high!

geek_jhan, Aug 24, 9:26 pm

geek_chnman, Aug 24, 9:42 pm

Great, that looks easy.

geek_jhan, Aug 24, 9:53 pm