Keep the original format IF you have the hard drive free space.
That AVI format is uncompressed; pretty much anything else has some compression.
If you don't have the disk space, I doubt if you will lose much if you use the H264 format.
Note that there are some AVI file types that are highly compressed (DivX or XVid) but I doubt that you have that issue.
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BoilerPlate: To posters who ask for help -- it is nice to thank the volunteers who try to answer your questions !
Anything I post unless stated with a reference is my personal opinion.