Friendly, just to clarify, you want the copyright below the navigation and content - but its not necessary for the copyright info to sit constantly at the bottom of the visible content on screen (like a floating copyright)?
If so it can be done with a slightly different approach.
Darren, firstly I hope you didnt take my post above as being personally directed at you as it wasnt, Im merely stating the case for using CSS over tables for controlling layout.
Taking your proposed scenario for a blind person on youtube where vision is the obstacle. Your absolutely right - there is no 100% way to ensure that all websites are fully accessible to users with assistive devices. However, there is nothing to say websites cant be made to be as accessible as reasonably possible. A possible solution to the youtube website would be to offer a text/audio based solution that is descriptive of the videos content.
Ofcourse on a public video site, the onus of providing the audio description is on the uploader so not really workable. However if it were a company website, there is nothing stopping the company providing an alternative text/audio description of a video.
I've had a similar question put forward about a website that sells pieces of art online - "what would a blind person be doing looking at an art site?" ...well they could be looking to buy a piece of art for someone as a gift, and could base their purchase on the descriptive text associated with the piece of art - I think we can both agree - probably not a common thing - but not impossible if accomodated for.
There is a lot of assuming on the internet
Your right that poorer countries arent as 'advanced' as the likes of the UK so your 'older browser' point is correct - assuming the website in question is intended to have a global audience. If however the website is aimed solely at the UK, then I guess we can spoil ourselves by assuming people will have a more recent browser