A few questions from a Newbie

1) Yes, plenty of folks incorporate a commute as training. The heart of your question, I'm guessing is the potential benefit? That would depend on what the rest of your trianing is looking like. A short hilly ride can be used for high intenity or easy recovery. You don't want to sabotage a run by going to hard on the bike, but at the same time if every ride is moderately paced you will plateau quickly.

2) You need to be comfortable in your race gear and make sure that it works. SO you do want to swim in your race gear before racing in it. That being said, there is no reason not have a separate training and racing gear. Some tri-specific clothing is not recommended for chlorine anyway. Baggy clthing will slow you down.

I am assuming that your "gear' is a swimsuit and goggles, and not scuba or something?

3) You can go to the USAT website and print out the regulations. I've seen lots of racers use compression style braces. I don't know about a traction brace.

4) If you don't train during the winter then you will see a decline in fitness.

Welcome to BT!!

For winter work, there is no reason you cannot take care of it all without a gym.

I go to the pool to get my swims in.  I run year round regardless of weather.  And I'll ride my trainer indoors for the bike.

Usually training in the pool is done in Jammers.  Tight long swim trunks that hold up pretty well to chlorine and can be had for cheap.  Check them occassionally to make sure they have not become see through.  Racing stuff gets expensive and doesn't usually last as long.

 You can train without a gym all you want.  Weights are not mandatory, but they help.  Living in Seattle, you should be able to run outside all year round and the constant rain helps with the smelly running gear!  Pools are always available for swimming and like you said, you have the bike covered.  If you want to get into it, you could pick up a trainer for indoor rides when the weather is icy for a prolonged period.

Excellent!  I'm a Total Immersion (TI) follower.  Search the threads and become enlightened

Best way to protect those knees from injury is don't overdo the runs (start easy, build gradually over time in intensity and distance), and allow for recovery days in between.  Also, avoid hitting the pavement with your heels - aim for using the balls of your feet, your knees will be grateful.

You'll find over time your knees will get stronger.

I tore my MCL last winter and have had to wear a donjoy defience III ever since for snowboarding, contact sports, mt biking, golf and anything that might tweek my knee.

I started training with it for the run, bike and swim b/c I thought I would need it for tri's. 
I emailed USAT regarding rules and reg for braces.  They are fine and can be used.  The only issue would be during the swim.  Because it is hard, it needs to be covered like it would need to be for any contact sport via a sleeve or under your wet suit.  For the bike and run, it doesnt need to be covered since there shouldnt be any contact (unlike the swim)

Thanks for the replys everyone. Most of my swim gear right now is just the long shorts spandex/lycra speedo (someone named it earlier but I don't know the jargon that well yet) and googles. Eventually I will be getting a wetsuit but I want to see how my swimming is after classes before I decide what style I want/need. As far as bike commuting is concerned I have many ways that I can work it in as a workout my problem is finding a way to get home/to work on my bike without it being to much of a work out. I have at least 2-3 (going or coming) steep hills on my route that are .5 miles long or longer, not to mention all the rollers and long gentle hills I climb. So I am wondering if having a hard ride 2 times a day 5 days a week will hamper my other training (legs to tired etc...) or if I will get used to it.

I also have a book that lays out for me how to structure my training schedule and about how much time I should allocate per event and unfortunately...bike commuting is way more than is recommended. I am also going to see my doctor soon (he has a strong interest in sport medicine which is why I choose him) to make sure doing all of this wont kill me. Again thanks for all of the answers and feel free to leave more information!