1. Yes, as long as you control the serious anxiety and depression that comes with it. The easiest way to control them is regular therapy (I was going once a week at my worst, now once a month). It just lets you work through everything because you do find large parts of the world incredibly confusing and very scary because of it. The first thing to do is realise that your anxiety is completely irrational, that for me was what let me destroy the anxiety.
In fact personally I see my Aspergers as an incredible strength in the workplace because it lets me process analytical thoughts at an incredibly fast rate, learn new concepts in a flash and gives me a cool detachment which is required in a lot of professional situations.
2. No, you learn coping strategies as you go through life and through therapy, there is a real drive at the moment to catch Aspergers in children because if it is noticed early they can start teaching coping strategies through therapy right from the get go to minimise the possible dangers later in life.
3. No, social anxiety is a symptom of Aspergers which is caused by a lack of emotional intelligence (social anxiety can also have a million other causes). This is only the tiniest little slice of what makes up Aspergers though.
4. Yes and no, medicine can be used to treat the depression and anxiety caused by Aspergers but it does not fix any of the root causes. Personally I had a bad experience when on anti-depressants in that they made me even more "emotionally dead". They keep you "happy" but your range of emotions gets slimmed down even more which is not a comfortable feeling. Of course everyone responds differently to anti-depressants and really there is still very little understanding of how anti-depressants work in any sort of complex levels of mechanism.
5. Aspergers other name is "High-Functioning Autism". A classic Autism sufferer is a person who's brain has not developed intelligence (IQ) AND emotional capability/empathy (EQ). Someone who has Aspergers has a highly developed intelligence (IQ) often surpassing the average population by a long way but at the same time a very low emotional capability/empathy (EQ).
6. If you have depression/anxiety issues the first thing to do is speak to a first line healthcare professional about it, they can refer you on to the relevant services which can then give you a more thorough diagnosis. You cannot really self-diagnose Aspergers because a) the symptoms are incredibly similar to PTSD and it is highly unlikely unless you are trained to understand the differences you cannot really separate them, but as both have such extremely different root causes they both need completely different treatment plans. b) Aspergers is a highly complex difference and it is highly unlikely you can understand yourself to the level that you could self-diagnose such a complex disorder.
Self diagnosis is for going "yes this is a blister on my foot, lets put a blister plaster on", it is not for "oh here is a highly complex and incredibly in depth mental difference, lets read some on-line resources and suddenly understand it as well as someone who has had 13 years training on the subject and has worked as a professional for X amount of years".
Aspergers is a lifelong disorder because it is simply the part of your brain which handles emotions and empathy has not grown properly and as such does not work to the level it should.