I'd like to give a shout out to two independent and well-done zombie movies:
American Zombie (2007) - Mockumentary about a Zombie Community. Really well-crafted and acted.
ZMD: Zombies of Mass Destruction (2009) - Lots of fun.
And as for personal favorites, I love Shaun of the Dead and 28 Weeks Later (if you want to call that a "zombie" movie vs. an "infection" movie).
Does Night of the Comet count as a zombie movie? Also adore that one.
The hubby watches and rewatches the Dawn of the Dead remake a lot, so I've grown fond of that one too.
Night of the Living Dead is such a classic to me; I had so many nightmares of being stalked by slow-moving corpses as a kid (I'd always climb trees to escape them - Can Romero zombies climb trees?)