1. When calling the second Death Star "fully armed and operational", I believe he was refering to the battle stations main purpose as a giant superlaser, which was fully armed and operational.
2. I always thought that you could specify how powerful the beam was depending on the target.
3. The Death Star I could move, it had 123 hyperdrive generators, the second one would have undoubtedly been able to move also had it been completed.
If it had been completed then it would have had more than the original, it was 900km in diameter whereas the first Death Star was only 160km. It was more formidable than the Death Star I even in its unfinished state.
"For where ever there is a n00b, there is MachineCult to make him cry and cringe."