Climbing as a support?

Support is possible

Any support that isn't high risk and high reward

Lane control and peel is all you have to do

I hit Plat as Nami, and many others have climbed much higher solely as Support (Challenger, even), so it's certainly possible. It's just typically considered more difficult because you tend to rely on the other players to be as good as you are or better.

You want to play what you feel most comfortable on. I do recommend a very aggressive playstyle in a kill lane (as opposed to anything passive), but playing what you actually enjoy will most likely produce results; I just suggest you keep that to a select few so you can master them. If you don't know what you want to main yet, practice everything in Normals first instead of trying 15 different champions in Ranked once each and losing them.

Well if you play as Taric you are guaranteed to reach Diamond V.

http://www.auplod.com/u/pdolua802d6.png

I think it's possible, you just need to know a few supports well and who they are good with. Certain supports synergize with ADC's or teams well. Kog'maw, for example, does really well with a Lulu (even before she got Attack speed buff) simply because she can cancel assassinations on him with her ult and polymorph and allow him to stand in place like he wants to. A good Jax with a Zilean support can easily murder the enemy ADC and get revived if the enemy team focuses him out. Or you can use Zilean to counter Draven by just placing bombs where his axes will land and ulting whoever he targets to negate his adoration stacks.

I personally like peel or pick ranged champs preferably with a heal. Nami, for example, can use bubble and tsunami to do both and offers a heal and speeds her allies when using abilities. Thresh can pick or peel though is reliant on his teammates clicking the lantern. Sona can pick or peel with ult, though she needs CDR to do it reliably since it's only one ability on a high cooldown, but she offers great poke if done properly and insane zoning potential. Morgana can counter for AP mages due to her spell shield alone plus that Q roots for 2-3 seconds and does a decent chunk of damage without AP items. Zyra, Brand, Vel'Koz, and Annie are decent pick/peelers but offer some AP damage if you need it in your comp. Karma is a good buffer and bait champion if you are good since her ult W offers great self heal and her shields can bait enemies or speed up allies to get kills/escape.

Soraka and Janna are my rare none pick champ who basically makes up for mistakes. Obviously you can make picks with them, but it's harder. Flash Monsoon can separate out a player from their team if they miss position or landing a Starcall can slow someone enough for her E to snare, but it's not as easy. Janna peel is insane and her shield can offer a behind ADC a good damage boost without items. And a good Soraka can heal and be running around at low health while the enemy team is still trying to kill the 1/2 health ADC or silencing the people who dive into their team or cross map bait heals.

The rest are mostly engage supports, which I've never really got, though they obviously have their place. All the supports that I mentioned above are generally squishy supports. If your team needs a tank, there are supports you can take, though they will obviously not be as tanky as a solo laner. Just find what you are good at and do what you can. Pick the right person to support. Try to protect your ADC but if you lose bot tower and your top laner is doing better, let the ADC farm and try to help them snowball more, or rotate mid and try to help the protect their tower since the enemy bot will probably rotate mid.

I highly recommend these supports if you need ap damage, like someone picked or and the top laner is also ad, either play or