I know a FEW of the answers:
embedded images... depends on how they're embedded. If it's Flash, forget it.
> 3. do they follow links embedded in a
> dropdown box?
Yes, as long as it isn't something in frames.
> 4. when an image is used for a link, do they
> check the size and validity of the image as
> whether pertinent to the link?
Nope. That would have to be done by a human. You could put up an image of a crocodile and have it link to a page on skunks and the robots wouldn't care.
Now -- your viewiing audience WILL care!
The Five Minute Mentor