Joomla site extremely slow

[Stingraynut]

This is a new installation of Joomla 1.6 with the database from a previous 1.5 installation that was hacked, so it all had to be cleaned.

I wasn't involved with the new installation but am now taking over and the site is loading incredibly slowly 15-20 seconds
http://www.webpagetest.org/result/111109...1/details/

There seems to be a long delay at the start for the 'time to first byte', I'm not sure what is loading there, hope someone here can help me understand the info and fix the problem!!

During the new installation, the site was put on another domain and then moved - I'm wondering if instead of moving it, it was redirected and that is slowing it down?

Rob