Question about buying a domain

I want to buy a domainname from someone.

The domain is registered in 04-07-2000. (4th july 200)

If the seller agrees on selling the domainname what will happen?

Does the domain creation date remains at 04-07-2000? Or will it be 03-01-2010.

This may sound stupid but I'm completely new to making and buying websites.

Another question:

How older the domain is the better it can get ranked?

As long as the domain you want to buy is not expired, the age of the domain will continuously increase. So, the creation date will not change. There is no relationship between the creation date and transferring domain from one person to another.

But if the domain is already expired, automatically the creation date will be reset to the the date of that domain was registered again.

IMO, for old domain I think there is no direct relationship with the rank. Supposed that the domain is just used for parking only, may be the rank is not as good as developed domain. May be you could check the history of domain first.

Hope this helps