I'll put it to you like this. I own every Resident Evil game (even the old PSX one with the huge case and Gaiden on Game Boy), so I consider myself a huge fan of it. Have been ever since I was like 10.
Now, if you've played RE 4, you know about the new (maybe? Umbrella MIGHT be coming back thanks to Wesker) plot with the Las Plagas parasite. Capcom decided to take RE 4 in a more action oriented direction (which was a pretty good move, I think. I just missed the zombies.), with survival horror mixed in (and that worked well. I jumped several times on RE 4, especially with the snakes in the boxes.).
Outbreak File #2 is a continuation of the original, but it's NOT a continuation of the original. I know that makes little to no sense, but Outbreak File #2 isn't a sequel for storyline purposes. Let's say that the survivors (Alyssa, Kevin, David, Jim, Cindy, Yoko, Mark George) all make it out of the bar (first level) in Outbreak one. That doesn't mean that they leave the bar and go to the underground lab (level two in Outbreak one). Outbreak 2 is more of a "What if?" game. What if the survivors had to escape the zoo? What if they had to escape an abandoned hospital, or an Umbrella Laboratory? So we don't really know WHO lives and who dies.
Certain levels pertain to certain characters. Alyssa, for example, is personified by the level Flashback in File #2, an abandoned hospital in the forest. If you're not playing as her however, you can get items from her (she's an NPC in this part), and then later come back to find out that she has turned into a zombie due to the T virus. This doesn't mean that she doesn't survive. It's just a "What if?" type of thing.
Outbreak File #2 is VERY similar to Outbreak 1, aside from the new scenarios, unlockables, abilities, and the ability to walk while shooting. If you're an old school RE fan who cares anything about playing a cooperative game online, trying to escape from Raccoon City, you'll ADORE this game.
Many people complain about 'n00bs' in games, but it doesn't bother me. I'm good with RE games, and I can beat them all, save Code Veronica, by memory. However, I can tolerate "n00bs" better than I can these people who are like 'OMG U GIVE ME STUPH IM AN EXPERT!111one', just because many serious new players are willing to cooperate and learn, and this makes for a satisfying and rewarding game experience. There's nothing like playing a scenario with someone, adding them to your friend list, then coming back later and picking up another game.
Apparently it's done pretty well, since File #3 is a certainty now.
But yeah..If you're into RE at all, Outbreak File #2 is a tad bit more difficult, so it's not as simplistic as the first one is. It has more of an old school feel to it, besides the online thing. Outbreak was good, but File #2 is by FAR an improvement over the first.
Besides, if you already own Outbreak and buy Outbreak 2, you can mail in a coupon and get 10 bucks back.