Dear Lord:D

Okay I assume that 720x480 is better these day because of 4:3 format is getting obsolete in term of HDTV and monitors?
Or may I have problem on the software side with 640x480?

In my case what I win by archiving in 720x480 instead of 640x480 if the MAIN pratical purpose is to play a MPEG-2 via a 4:3 projector?

Maybe I miss something and cannot see enough far in the future? (like when I learn that Huffyuv codec was better choice for archiving on the long run).

Right now when I encode my 720x480 AVI file to 352x480 MPEG-2, I can see via Adobe Media Encoder ouput windows that I will have black side edge because of the different ratio.

Thanks

More like 3:2 storage of 4:3 videos is more standard, and wasn't always in the past. It really has nothing to do with HD.

DVD = 720x480, so archiving as that means less aspect changes. It's not horrible, but avoid it when you can.
But if you're archiving as 352 MPEG, then it doesn't matter -- you'd be converting aspect either way. So 640 and 720 are both fine.

I don't see anything wrong with what you're doing.