10 Jan 2008 at 07:36 - 14
Much of the advice given here is excellent. I'm a lvl 20 ranger myself, and have been playing for nearly 3 years now. There are quite a few viable ranger builds for R/N's, though at your level/game progression you're often better off focusing on your primary class. (One reason this is true is that at lower levels minor runes are particularly useful, and you can only use runes for your primary class.)
In general, the best way to go is focus on one of the things your primary class is good at, which ties back to the "Don't spread your points so thin" comment a number of people have already given. Rangers, for example, are generally used for trapping (you don't have the skills to do this well yet), beast mastery, or as a midline damage-dealer. The last is by far the simplest and easiest for a new player to work with, so I'd suggest that. Thus you want to focus primarily on Marksmanship and Expertise, the two attributes that let you deal damage and keep dealing damage, respectively.
The secondary class, unless being used for a specialized build, is generally used to fill in gaps in the skills available to your main class. For example, rangers have no easily-useable direct heals (only a healing "trap", which is easy to interrupt, a few beast skills you can't effectively incorporate into non-beast builds, and Troll Unguent, which gives you health regen, but no direct healing.) Thus you might fill in this gap with Consume Corpse, Parasitic Bond, or some similar Necro skill. Other examples - Hexes to provide debuffs, which Rangers are devoid of other than conditions, Suffering or the like to provide an AoE effect, or something that synergizes with some of your Ranger skills, like the Elite Necro skill Virulence and any of a number of Ranger skills that apply conditions.
I've found that at mid-range levels, where you have enough skills to form a working build without having to delve into both professions heavily, it's often most effective to use almost exclusively skills from your primary profession. Needless to say, if you need to cover a weakness or have a Necromancer skill that works better than a Ranger skill for something, use it. But keep in mind that the more you have to split your attribute points, the less effective your skills will be.
BTW, my IGN is Fury Incarnate - PM me in-game or on Guru if you'd like help designing a build or learning some playing tips from a pro ranger. (Or if you need mission help or a hand with gear - I have more than enough time and money, and I'm always happy to help a new player.)
PS: Don't underrate defense. The bar you're using has no defensive skills in it, but Whirling Defense is one of the best Ranger skills in the game, and the ranger has a number of other, similar skills depending on the situation.