Is this server the same as Molten-WoW?

If you played when it was Molten, there are a few things that are different now. You would have lost all of your characters when the Moltdown happened and it became Warmane. If you were a donor you would have ha a small window of time to receive some compensation for the loss. You should be able to go to your account management here on the site and see if you have any coins available..

As far as the servers go, I play WoTLK mainly and noticed the core is different, some different bugs compared to before but still the best wotlk experience and high population servers you will find. Lordaeron is still a 1x rate server and Icecrown is a x7 rate XP server. Not sure with the other expansions. Either way I would like to welcome you back and hope you have a great experience!