It depends on whether you really want the army or not. If you do, then yes, get it, if not, don't waste your money.
And if by get you mean steal, don't.
The Vampire Counts are extremely effective in games of Warhammer, although they do take a bit of practice to master.
with skill and a touch of magic :)
Sure you can. Dwarfs are hard to beat, but you have greater mobility, better magic, and you should outnumber them. Vampires are currently a very difficult army to play (the change to 8th edition wasn't kind to them), but there are always ways to be creative and outmaneuver your slower opponent.
If you are serious about Warhammer 40K you can only play Orks.
You'll find the answer in the Warhammer Rulebook or in the army book you are playing.
AnswerYes! In Warhammer any army can beat any other army. All it takes is some good tactics and a bit of luck.
AnswerYes.
A warband if you play warhammer
Necrons
There is no "best" race or army in either Warhammer or Warhammer 40,000. They are all equally balanced so that players will not choose them based off of which is simply the strongest, but by which one best fits their playstyle as each army has a very distinct way of fighting and everybody is sure to find at least one that fits them.
Answer It depends on your preferences: When choosing an army consider its tactics/playing style or just if it looks cool. Do you like hordes of aliens? Then collect tyranids. etc.
No, but it always looks a lot better if your army is matching, and your opponent with appreciate it.