Following the style of the movie, I'd go for:
1. Endurance. Whether it's outrunning the shambling undead, or staying awake to guard your camp, or going without food and water for days in a zombified wasteland, Endurance is the most important skill.
2. Beware of Dungeons. Yes, sometimes every adventurer feels the urge to go loot a dark, cramped structure with only one way in or out, but you should know better than to risk being trapped by the ghouls.
3. Saving Throws. More so than normal, in D&D zombieland, a single save can spell the difference between reaching that next short rest, and becoming the stunned, restrained, combat-advantage-granting next feast for a horde of zombie minions. Get whatever bonuses to saves you can, and figure out how to grant yourself as many as possible. Also known as, "Be friends with a cleric." (because for some reason they can't grant themselves saves)
4. Radiant Damage. Would just an extra 5 damage have killed that mohrg that's proboscis-ing out your internal organs? Do you wish you could keep that homebrewed troll lich from regenerating this turn? Get yourself a sunblade, my friends.