DDO is a very min-max game, but it's not very difficult over-all once you get rolling. But a few things (traps in particular) require an all-out investment.
Given that you are new, and we yell at JM for jumping up and down at the trap box, to be a trapper, you'll need max ranks in Search, Spot, and Disable. On a Cleric or Favored Soul, that would be 2 points in each skill. As a Caster, you'll also want max ranks in concentration. So total you would need 7 skill points per level. This would mean basically you have to have an 18 INT Human Cleric/Rogue.
TBH, if you want to do a healing trapper, I would do a Bard/Rogue splash. Bards have solid healing and buffing abilities, and can be built for strong CC or strong melee as well. They also get extra skill points per level, which means you can choose any race.
I don't recommend buying Drow, since they are easily unlocked in-game. 400 favor goes by very quickly. Humans can be useful with the extra feat, Dwarves have more CON but a penalty to CHA. Halflings have a penalty to STR, but this is really not an issue, other than certain ailments like Enfeeblement being more likely to make you helpless. Elves have a penalty to CON, but at max level it's only -1 fortitude save and 28 fewer hit points. Made up for one of the better Dragonmarks. Other races are buy-to-play.
Unfortunately the character planner has yet to be updated, so newer changes such as the Swashbuckler tree and the Bard revamp aren't even in it yet. So it's a little harder to plan one out. Always take Rogue as the first level, since you get 4 times the skill points at first level when making a new character.
Basically, always max out Search, Spot, and Disable Device every level. Use Magical Device (UMD) is also awesome, if you can afford the skills. For casters, Concentration is a must, and if you can Heal (to boost healing spells' strength) and Spellcraft (to boost damage spells' strength). Perform is a must for a Bard.
Going with a splash, you may not be able to fit in everything on a 28 point build. When I had a trapper Bard, I put everything into UMD, Search, Disable, Spot, Concentration, and Perform. I think I needed 9 skill points per Bard level, which meant I had to have a starting INT of 16 (she was a Half-Elf). I have stat tomes on that character, so she used the extra skill point later to shore up weak spots.
Rangers are actually easier to build trap skills into, since they get Search and Spot as class skills. Their healing ability is more limited (don't underestimate it though, my classic Exploiter served as tank healer on a few raids), and buffing is definitely limited. But they gain Evasion, all three Two Weapon Fighting feats, and most of the best ranged combat feats letting them be versatile in combat.
