I will say something on each of the four mechs from MY point of view. This is my personal oppinion, not the ultimate truth (i guess)
Jenner: You can run around (and away) rather fast. You even have a decent punch, But if you end up in the wrong place (in front of bigger mechs) you are screwed. A fast mech is all about knowing where you are, knowing where the enemy is and knowing the map. Not what I would usually recommend for a beginner. But if you like it, try it.
Hunchback: I do not like the Hunchback. For a mech of this size you are slow. You weapon are all short range. Your armor is ok, but you are still a medium mech, not too much to expect here. And everybody knows what you can do (AC20 is more or less your only weapon). Excellent for close quarters (cities), rather poor in open terrain.
Catapult: My personal favorite. Standard speed for a heavy with added manouverability due to jump jets. Excellent support mech. The supporting role is what I would recommend for a beginner. If you do have a proper command structure you get your targets named for you, your job is to observe and position yourself. You can see what the others do with their mechs and learn from it (especially the mistakes

). And if one of the small mechs gets too close, you can still depend on recent armor and som medium lasers. But that will be a hard time for you...
Atlas: I think this mech will be easiest to pilot for the first two or three games. Lots of armor and weapons, you will survive for quite a while. BUT: you are big and slow and probably the prime target for all the enemy team. You are always in the thick of it, you only get some rest if you are out of position (which will probably result in getting your team killed and you swarmed by the enemy afterwards). But it will be very hard to improve with this mech as a beginner. Best point for the Atlas: He is one of the best looking mechs in the game!
As I said in the beginning, this is my opinion. I personally will go elite these days with a Catapult. I just love these LRMs.
Hope I could be of a little help. Have fun and see you on the battlefield.
Edited by Boldar, 25 June 2012 - 11:02 PM.