If you have 2 separate domains, they can stay as separate domains.
One example use of a subdomain is to create a "free" dreamhosters.com subdomain, like mytestarea.dreamhosters.com or http://blog.dreamhosters.com/, and use it for experimenting, in addition or in place of your "free" domain.
You can get IPs for each domain, at 3.95/month. http://www.dreamhost.com/hosting.html
You'll have to "register" each domain; I'm not sure if your "free" one can be .uk.
[color=#00CC00]ANONYMOUS0=>Max Discount[/color] [color=#6600CC]ANONYMOUS2=>Max - $1.[/color] Being mean doesn't make you look smarter than him. And bigoted remarks are not appreciated on this forum.