uploading videos that work

Hi,
I’m am using a MacBook, System 10.4.8.
I’ve been working with a program called Cinematize, making small Quicktime videos to upload. I’m really struggling with trying different codecs within the program because all of the movies work fine for me when they are uploaded, but they don’t work for some of my site members. I tried asking the software company’s tech help and that very unhelpful guy told me to go buy a book on video compression.

I’m trying to find out is which codec and output format to use. My host will not allow streaming video, so MPEG-4 did not work, but I have plenty of other small Quicktime movies that work fine. I’m also trying to keep the file small, for quicker uploading time. There are a LOT of choices of codecs and I don’t know what they do. For instance- VC H.263? DV/DVCPRO - NTSC? Sorenson?

I’m trying to accomplish one thing - create small file size videos that will play for everyone, not streaming. I know it’s possible, but I haven’t figured out how.

As you can tell, I’m a very green beginner, and I would appreciate any help.
Thanks,
ThatGirl