If you haven't seen the first one you have to at least know someone who has and you have to know it was painful to sit through. There just wasn't anything good to say about it at all. So what's different with the second one? Why bother making a sequel for a movie that was wretched? This one doesn't take itself too seriously. It knows it was made for TV and doesn't try to impress with great or serious dialogue. There are moments where it tries to get 'serious' or 'intense' but these moments are so corny you have to laugh.
Thankfully gone are any elements of Uwe Boll and any hint that this originated from a video game (other than the title of course). Don't go into this movie expecting anything worth mentioning to your friends unless they're into camp, lame zombie movies, or are interested in making a drinking game out of this movie. Take two shots whenever Ed Quinn's character mentions his dead brother! Take one shot whenever a bullet would have been better place in the head of a zombie instead of pumping three in the chest! etc etc.