Basic Ranger interrupter.

Skills:

incendiary arrows {E}
chocking gas
hunter's shot
savage shot
distracting shot
whirling defense
troll unguent
res signet

attribute points:

More than one choise here

1. more damage from arrows
to get this you need all attribute quests done and have the following items
-superior rune of marksmanship
-mask with +1 marksmanship
-minor rune of wilderness survival
-minor rune of expertise

Expertise 10
Wilderness Survival 10
Marksmanship 16

2. for longer chocking gas, more healing from troll unguent and longer burn from incendiary
to get this you need all attribute quests done and have the following items
-mask with +1 wilderness survival)
-superior rune of wilderness survival
-minor rune of marksmanship
-minor rune of expertise

Expertise 10
Wilderness Survival 16
Marksmanship 10

You can change the attributes to your own liking, I'm just giving 2 examples of the extreme.

For both options you will also want to have a superior rune of vigor, those however are very expensive in pve.

weapons:

I suggest getting a short bow as a first weapons set and a long bow as a second weapon set.
the mods are up to you, right now I'm using sundering ... of fortitude on both of my bows.


Tactic:

target priority goes something like monk/mesmer/necro/ele/ranger/warrior, mesmer and nec can be switched depending on their build.

when starting and close to being in range of enemies cast chocking gas and start attacking a target.

When chocking gas runs out cast incendiary arrows.

when the opponent is running away or knocked down use hunter's shot so that the target starts bleeding.

just use the savage shot and distracting shot whenever the enemy is casting an important spell/skill like for instance a res or big healing, because you wont always interrupt with chocking gas and incendiary arrows alone.

When you're getting physically attacked just throw up whirling defense and cast troll unguent, and if you really have to, start running.