What will your budget be? That can be a determining factor.
As for "best" engine to swap, that's kind of subjective. Do you want an engine that will swap in easily, look like it came with the car stock, and provide about a 50 horsepower boost over the current engine? If so, then the H22 is where it's at.
If you've got lots of cash to burn and you don't mind a more difficult and involved swap, then I'd say look into a K-series engine, probably a K24 from a TSX specifically. That engine will make 200+ horses, have pretty decent torque (for a Honda engine anyway), and will respond very favorably to bolt-ons and tuning.
Like I said, budget and your ability to do the work are going to be key here...