Recommend a class which will do the least harm!

[Hestzhyen]

RDM as people said, or you can try Bard as well.
Support abilities, high moblity and not very complex rotation (based on proc with dots)

BRD has a low skill floor but by the time you get close to 70 you will be tracking a lot of different things; it can be quite hectic (at least in my experience). It's not as convoluted as MCH or SMN by a long shot (hah) but just keeping track of everything during an active fight can be a bit overwhelming.

If you want low-stakes, WHM is very easy- straightforward to play, tons of raw power, and great at turning around a scary fight. Healing in general in this game is actually pretty easy until you start doing EX/Savage content. There's a few bumps on the road to 70 but they aren't outrageous - if you err on the side of caution and know where your "srs bsns" buttons are you'll probably be fine.

[AmemeAmeklin]

As a new player who started out as a marauder, here is my basic experience:

It does start out pretty simple and The Smith lessons are super helpful. It took me some time to get to 50 since this was before the MSQ exp boost, so I was given more time to learn. The rudest comment I got was 'why on earth wouldn't you use tank stance' in one mid-level dungeon, which is not rude at all (of course I'm sure they complained about it in private later). That was when I learned about stances!

That said, you need to have fast reactions if you start out as tank or healer, not to mention a thick skin because there are some buttheads out there and tanks/healers are easy targets. Otherwise, the safest type is gonna be one of the long range DPS classes (archer or thaumaturge or arcanist) just because it lets you stand away from the action somewhat. Fights get more demanding later on no matter what the class, so be ready to learn and experiment and ask others for advice!

(PS I still do stupid things as a tank like chase butterflies during Ravana but at least I don't fall off the cliff on Titan normal now. Progress!)

[Dhaid]

A class you can constantly mess up on and everyones fine with it? A dps is the easiest to get away with this, but no matter who you pick if someone is looking for faults in others theyll find them. DPS parsers let others know how everyone is doing, and are allowed by square as long as you dont rub it in other peoples faces.

What im trying to say is, play what you want. I had a friend go from pugulist/monk to black mage since they werent having much fun 60-70. This was after them playing monk all of 1-60. I play mostly warrior, but ive been playing summoner cause theyre also fun. Play what you want when you want.

[Squintina]

Pretty much everything is viable, especially for leveling content, that it really doesn't matter what you pick

That being said DPS classes are considered to be less stress than tanks or healers, but they have longer queue times. Tanks and healers have shorter queue times, but people like to blame them when runs go wrong, even when it's not their fault. If the run goes well though, it's usually a guarantee of getting at least one commendation.

If you're willing to take on the extra responsibility, I will always recommend starting as an Arcanist and making proper use of its ability to be both a summoner and a scholar.

This will allow you to do the solo quests as a summoner, and get fast queues as a scholar. If you're doing that from the beginning (well, from level 30+), dungeons/trials should happen enough that you never feel like you're just jumping to scholar without knowing how to play it (it's people that wait until they're 60+ or 70 that generally have that problem, but someone that switches back and forth from the get-go typically will have no problem playing both equally well).