Even though this game is 10 years old (as of this review), this specific game is a great intro to 2D Fighting.
Storyline: Non-canonical, just like the entire series.
Gameplay: The game control's simplicity allows it to be picked up fast, while steadily learning each and every character's respective moves. In addition, the fast-paced action reels you in.
VS-wise, it is a wide range. I actually got a 5-win streak on PvP matches, while playing as Roll & Captain Commando, while most people would pick dialers and beam hyper whores.
Graphics: 2D, as an art form, flourishes here. They're clean, well-defined, and well-drawn. In addition, every stage gives references to either a Marvel or a Capcom-related stage. New York rooftops for Spiderman, the Japanese bathhouse from the SF series, Dr. Wily's base from Megaman, and even Stage 1 of Strider, re-done in full 2D!
BGM: except for the hidden character BGM, every single character's is either a remix or a brand-new piece. Old-school Megaman 2 theme and Raid!, Stage 1 of the original Strider game have been remixed, while Jin and Morrigan get original pieces.
Sure, MvC1 is ten years old (as of 2008), but overall, I love Marvel VS Capcom due to the fast-paced action, intricate attention to detail, and the personalized BGM, as per character in the standard roster.