[selven]

Anything that doesn't travel at 299792458 meters per second will not be a viable weapon in space. Two spaceships coming toward each other will be hundreds of thousands of kilometers away when they start firing on each other. The time lag will be over one second for lasers, so if the two ships are maneuvering randomly many laser shots will actually miss. Kinetic weapons will take minutes or hours to get there, making them essentially useless. With missiles (I'll assume missiles are nuclear here), not only are they slow but you can also set up computer controlled lasers to fry their control circuitry. Nukes require very specific detonation conditions and if you fry the explosive material it won't explode like a conventional weapon, it will just fail.

Also, with ships punching a hole in the bottom is enough to sink one - most ships hit by a one-shot-kill missile take a few minute to do down because they're sinking, not exploding. In space, this doesn't exist. You have fuel tanks and engines, but those can be safely put at the back of the ship, and in a battle you'll just rotate your ship so that the front faces the enemy.

[InclinedPlane]

Consider this: an unmanned missile can accelerate much faster than a manned spacecraft, so it can evade laser fire much more effectively as it approaches the enemy. At a critical distance it launches its payload: hundreds or thousands of tiny (e.g. 10 gram or so) fragments distributed in a grid (at a density of, say, 1/m^2 distributed over as much as a km^2 at the interception distance). These intercept the target at 10s, 100s, or 1000s of km/s. Such a weapon is hard to defend against, even with highly effective lasers, and is devastating to the target.

[selven]

I would imagine that depends a lot on what the distance is. Release too close and you get blown up by a laser before you can release. Release too far and by the time they get there the ship will have moved away.

[qw]

The missile will be smart enough to compensate for ship movements.

[selven]

I don't mean the big missile, I mean the payload that InclinedPlane's strategy described - a missile shooting out a few thousand mininukes a short distance away. Such small payloads, even if we give them engines (which also makes them shine brightly to anti-missile lasers) are simply too small to outrun a ship - small engines tend to be very inefficient and slow.