What's the best engine (to add horse power and torque) that i can swap into my 1999 Honda Prelude?

Currently i have an H22A but i heard that the k series or even the f series are better? Is this true or should i just stick with my H22A?

H22A makes close to the same specs as the k20. The only difference being the transmission gearing is different, and it revs a lot higher than the h22a, and is also more reliable, but there's no point in swapping engines, and there's no point and doing anything more than bolt ons to an h22a, they can't handle much more than that. If you really want to get into swapping, drive that car and have a civic or integra and swap in a b18c5 or k20 into that. A prelude is too big, heavy and already has a decent engine in it to even bother doing anything to.

Why would you swap motors in a 1999 model car? Sounds ridiculous to me.

A 1.21 Jigawatt Mr. Fusion generator with appropriate accessories and cooling system.