Class

It's a 'Image' of a file, you can use tools like Daemon Tools to 'Mount' the image and it will look just like a normal CDROM in Windows (or whatever OS you are using.) Most Linux distros comes as ISO images, that can be moved around like a normal file, and be 'Mounted' to install from it. Edit: Many CD-burning software can open ISO-files and burn them.

Yes you can, just not for making dynamic sites with WebDAV.I tried NetObjects a few years ago, but didn't like it, the output code was messy and bloated (it used pixel-stretching for accurate placement.) It was really easy to use though. I would really consider Macromedia's Dreamweaver instead.

Possible with a shell script & cron perhaps?