wtf is dark energy and why is is better?

Although solar sail technology is the only one in this poll to be of any use, not too mention a beautifully elegant and romantic idea, it's too impractical and weak to of great use. Sail sizes required are too large and are themselves too easily damaged. And while the sun's light is powerful close to it, a sail wouldn't work well at all past Jupiter.
The spacecraft propelled by nuclear explosions was very nearly built in the sixties. Project Orion was a US program to eventually build a nuclear-sub like spacecraft propelled by nuclear explosions (this was thought up in the days when plutonium seemed ready to solve all the world's problems). It got quite far along, with the propulsion method well-investigated, and other necessary technology already available. Unfortunately, incorrect ideas about the 'purity' of space raised ill-founded concerns of contaminating space with radiation, and the project was cancelled. And no one wants nuclear-powered craft these days.
The dark energy warp drive may sound good to fans of Star Trek (one of which I am not) but sadly it would need cosmic-scale energy, equivalent to the gravity field potentials of entire solar systems to be of any practical use at all. So unless we can store entire stars on a ship, this is not helpful.
The hyperdrive, in theory, is the most - and only - practical FTL system. It requires relatively little energy or machinery, and is robust. However, although a yet-to-be-falsified experiment lends support to the theory behind it, it is based on entirely unproven physics, and no one is willing to risk money and reputation on something no one understands.
In the end, none of these is very likely to lead anywhere in the near future.

I'm sure that anti-matter will provide the enegy for fast spacecraft propulsion. The are 3 tasks required.
Firstly to produce the anti-matter. We can already do this in random circumstances but we need to find out how to do it consistently. I expect it will involve fine tuning a high speed particle accelerator.
Secondly to confine the anti-matter to some sort of magnetic or other force field so the antimatter can be carried into the spaceship.
Thirdly we need to bring the anti-matter in contact with matter in a controlled situation that will direct the force in the opposite direction to the direction of travel. This may be a case of releasing the anti-matter in that direction.
The force released will be much greater that that from small nuclear explosions.

Wow! These starship engines are great! We can use them to put pie in the sky and castles in the air!

I cannot understand why scientists waste millions of brain cells pondering the means to invent a "faster than light" drive for spaceships when that is obviously not the end we need to attain. Consider this: Even at the speed of light, it's always dark until the light arrives. Ergo we need to invent a "faster than dark" drive. Alternatively, if we can find a way to pull the strings using the vibrations of people asking us if everything is okay, we should end up with a "whatsamatter" drive.