Or if you don't want to edit all your files to change the services.html to proof, you can add a redirect to your htaccess file to something like this:
redirect 301
http://foo.com/services.html http://foo.com/proof/
So whenever someone goes to services.html they will be redirected to proof
Btw I have to tell you what sam said is better than this solution!
And if you want a url like this: freebiesforme.co.uk/about/why
create a folder called "about" under your root folder and then place the why.html/php in that folder.
So the url will be freebiesforme.co.uk/about/why
I am sorry if I misunderstood you! :/