Think I'll get around to checking out some more Iced Earth.
I'd start with Alive in Athens and follow it up with Live in Ancient Kourion. Both are excellent representations of the Barlow and Block eras.
From there, here are the albums to check out:
Something Wicked This Way Comes: Arguably their best album and one of the few that has absolutely no filler.
Dark Saga: Perhaps my favorite album from IE, this is a concept album based on the comic Spawn (with cover art drawn by Todd McFarlane)
Horror Show: Another concept album, this one based on monsters (werewolf, Dracula, mummy, etc). It's a hit & miss album, but when it works, it really works (Dracula, Damien, Jack).
Glorious Burden: Their first album with Tim Owens, this one revolves around the theme of U.S. wars. As with Horror show, there is plenty of filer, but enough works to make this one worth listening. In particular, check out Declaration Day and Gettysburg (1863), the latter of which is a nearly 30 minute epic.
Dystopia: Their first album with Stu Block, this one marks a return to form after its mediocre predecessors.
Incorruptable: Their latest (and possibly last) album, this is the first one since Something Wicked that doesn't have a main theme, and the freedom makes for some very good songs. While it does have a few filler songs (Brothers), it also has some awesome tracks (Black Flag, Raven Wing, Clear the Way) and is a fine album to go out on if it does turn out to be the swan song of this band.
BTW, if you like Iced Earth, you absolutely must check out Demons and Wizards, the side project of Jon Shaffer, with Blind Guardian singer Hani Kursch. The S/T debut album is arguably one of the best albums of 2000, if not the entire decade, it is that good.