Aikido- it's all good!
James, like the others, I believe that practically anybody can benefit from practicing Aikido. If you practice from your heart it can be a quite a world- changing experience. Aikido is an entirely new way of viewing the world, conflict, people and relationships (of whatever kind they may be) and our place in them. So, go ahead, try it! Even if you find it's not quite right for you, you'll walk away enriched by the experience. But, I'm biased, so don't take my word for it. Still, research the different schools in your area. The dojo search engine in this site gives good info as to the more reputable schools open in your area.
Although Aikido does use the body's pressure points (particularly as targets for atemi), this is just a small part of Aikido's self defense technique repertoire and potential. However, you will come to realize that Aikido is far MORE than just self- defense: its fundamental goal is to create better, honest, earnest sincere people through the discipline of a martial way.
A "dojo", or "place of the way" in japanese, is where you will learn the Art; basically where you go to train and learn.
BJJ does indeed stand for Brazilian Ju-Jitsu and it refers to the Ju-jitsu styles that originated from the Gracie Jujitsu school created by the Gracie family of Brazil. It is something of a misnomer because, from what I understand, it was developed and refined from a classical Ju-jitsu style (I don't recall the name) taught to the Gracie Brothers (Carlo and Helio Gracie) by a japanese ambassador in Brazil. The Gracies then elaborated on this style and called it Gracie Ju-jitsu. People then started calling it Brazilian Ju-jitsu when schools of this type of fighting started popping up. Incidentally, I understand that the Gracies themselves guard their techniques and teachings very jealously and to be a Gracie Jujitsu instructor you must be certified and licensed by the Gracies personally.
Still, calling it Brazilian Ju-jitsu is a misnomer. It'd be like calling an Aikido style that originated in the U.S. "American Aikido". It's still Aikido.