HUGE file webinar downloads

Hi,

My client wants to sell several 35-50 minute webinars in her zencart store. I'm wondering if anyone has done this that can talk me through the process.

- If I make the file downloadable, it is HUGE, and I am concerned about the customer's savvy and time-out errors.
- If I zip the file beforehand, I am concerned about the customer's savvy on how to unzip and having the appropriate software to do this.
- If I put each webinar on it's own webpage and provide the url in the checkout process, the url
can be shared with other people, which we are trying to discourage. If I password-protect the directory and change the password every month, then the customer wouldn't be able to review the video, which they purchased.

Other than doing this via a CD, does anyone have any suggestions about either making the file a download or securing a webpage for online viewing?

Has anyone worked with such lengthy files before?

karine
using zencart 1.3.9