So I played a little of the first game but could not really get into it at all. However, my friend told me number 2 was VASTLY better and different, and not as repetitive. I'm thinking about purchasing 2 and 3 and just researching more of the story from the first game. I really enjoy the Arkham games and 3rd person for the most part. Is this a worthy buy for me? I guess it'd be like 80 bucks for both.
Both games are great and I recommend getting them. You'll be confused with the present day story though if you skip over Brotherhood and Revelations (aka AC 2.5, AC 2.75). I originally got bored with the first AC but still finished it and wanted more of the story. AC2 adds a lot of improvements and mixes up the gameplay. Each game since 2 has added more controls and freedom to the player.
If you can buy all of them or at least rent, watch a playthrough or something to catch up with the story then you should.
If I were you, I'd just suck it up and play the first one til the end. For me, even if a game isn't as strong as its sucessor, I just can't see myself playing a sequel without experiencing its predecessor, whether or not its story orientation is strongly, or loosely affiliated.
To answer your question if it'll be worth the buy or not.. Hmm.. Sure, I'd hit it.
"This issue doesnt concern you. Dont Bother me. Die..."
You can watch just the stories for these games on youtube. Its about 4-5 hours long per game. The series does get a lot better with 2 (1 is very repititive and each game gets a little better at being more organic as far as the flow of game play), but it may be worth watching the cut scenes for the first one to get a grasp on the story.