swimming for fat and injured runners (lots of questions)

Hey! To keep a long story short, I started running a few years ago, ran a few marathons, and now am horribly injured in the foot (Plantar Fasciitis). I've had it for about a year and a half, tried EVERYTHING, and have gained a more than significant amount of weight since I got it. I believe the excess weight is preventing me from making a comeback. Anyway I have been unable to stick to a structured diet and training regimen without a sport to train for, and I have been unable to run with any consistency. This has created somewhat of a disaster. I have decided to look for alternate sports, at the very least until I am at a competitive weight for running, or if I like it enough, possibly permanently. Swimming appeals to me because of the fact that it isn't very gear dependant (cycling is OUT), and because of the low chance of injury. I also really like doing sub-threshold and vo2max workouts and would absolutely love to do them everyday. The thing is, I have never swam other than recreationally in my life. I don't know the strokes or techniques at all. Does this sound like swimming would be a good candidate sport for me? Can I swim 6-7 days per week (after acclimatizing myself to it)? Can I do hard work every day? Is it like running/cycling where you have to do lots of base miles first? What kind of supplementary exercises make a good swimmer? I've never set foot in a gym in my life, and like a true runner, I have pitiful upper body strength. Can I get all of that from swimming, or do I need to start weights too? I am used to training with a Heart Rate Monitor, can they be used for swimming, or is there a better way to train? I am 6'5" with a HUGE frame. This is somewhat of a disadvantage running, how will it effect my swimming? Any good books on the subject for beginners? Can I just show up to a masters class in jammers and goggles, or do I need to do anything to prepare beforehand? There are several short course pools which have masters classes in my area, I can't seem to find a long course pool though. Will a SC one be OK? I am by no means interested in becoming a sprinter. Thanks, and sorry to bombard with questions, I may have a few more later on. I wish I could contribute something in return.