If you're getting really into it I think NHL.TV is a good buy but if you already sub to premier sports for other things maybe just stick with that until you want to watch all the games from 1 team.
If you only watch NHL on there maybe look at getting NHL.TV instead.
Just follow a team you like to watch - for their style of play. If you enjoy offensive speed/skill - teams like the Penguins, Sharks, Lightning, Stars, Blackhawks are good bets.
If you want entertaining, high scoring games with some insane skillful plays, and horrible mistakes all from team watch the Flames./Bluejackets
For a more balanced team, the likes of Capitals, Blues, Ducks are good.
Honestly though you can't go wrong with most of them - then just see who you end up preferring naturally.