i'm submitting two of my films, and just to make it easier, should i put both films on the same tape or on different tapes? Or does it matter? By experience, how long does it take for the film to get posted on the site? Thanks!

You can put both films on the same tape. That's fine.

When you submit your film, you'll be given a date for when it will be posted. It usually takes a few weeks, but it varies.