Wow Dungeon and raid title guides
Champion of the Frozen Wastes is easily within every player's grasp these days, although it was a bit tougher back when Wrath originally shipped. Getting a kill on every end-boss in Wrath heroics will happen eventually through the Dungeon Finder, World of Warcraft Gold and if you're sufficiently patient, eventually Malygos and Sartharion will turn up as weekly raid quests too.
Getting a Kel'Thuzad kill will be the real sticking point, as Naxx just isn't run that frequently these days. You should be able to convene a group of like-minded souls to scrape together a kill on some idle weekend, and I believe it's now possible to skip most of Naxx and go directly to Frostwyrm Lair.