Site got hacked and defaced :(

Yes, they put a hash leaf and a brazilian flag there, with some rock music!

Well anyways, I looked at the cached site in google, and copied the source code from there minus the google stuff at the top.
Pasted this into the current defaced index.htm file and managed to remove the damage.

However, none of my links work on my main menu.
I’m no genius with php etc, but anyone have an idea what could be wrong and a possible method of rectifying it?

Site: https://www.robertemmett.co.uk

Thanks a million,

Emmett