Self-taught vs. Classroom?

This is a debate I have with myself often. I am a learner. I find great pleasure in learning new things. But with a life chock full of responsibilities I don't have much time for classroom learning the way I used to, so I have been forced to explore other avenues of learning.

I am currently attending Ellis College. Ellis is the online portion of the New York Institute of Technology which is a typical, "brick and mortar" college with a few campuses in various locations in New York. Through lots of life circumstances (and a few bad decisions on my part) I was unable to pursue a typical college education right out of high school. Now, with a house, two cars, and various other bills, working a full time job is essential, which left me unable to attend college during the day. There are a few universities in my area that offer evening bachelors degree programs, but most them were very specialized (i.e. business) and would take me so long to do that I would be 50 before I had my degree. I decided at that point that online was my only viable option.

Online learning can either be horrible or great, depending on the institution. Ellis tries very hard to make their online learning environment as interactive as possible. It is one of the best online learning institutions that I have encountered. But, online learning still has its faults. It is a very self-motivated venture. If you are the type of person who needs someone looking over your shoulder and reminding you to get stuff done, then I do not recommend online learning.

I am also teaching myself web site design from various books. This has proven to be a much more difficult thing that I originally thought it would be. Turns out that most books on this subject are so confusing I feel like I'm reading a foreign language. I have managed to find a few that are easy to understand and I'm enjoying the progress I'm making in that area (which, in all honesty, isn't much - but you gotta start somewhere right?).

My whole point of this rambling on is this: What do you loose, from the education experience, when you don't learn in a classroom with other people and an informed instructor?

I'm wondering because I want to start practicing yoga. I need to be doing something physical and I also need to learn how to be calm and tap into the more spiritual aspects of universe. I've always been fascinated with yoga, but could never bring myself to get started. Now I'm ready to tally forth into the great blue yonder, but I have a dilemma:

Do I take a class somewhere or do I buy a book, or a DVD, or use one of the millions of free online resources?

If I take a class that will cost money. And I can probably only afford to go once or twice a week (if that) and I would have to fine time to fit that into my schedule. But I will have the benefit of motivation (I am paying for it after all) and of having someone physically there to tell me if I'm doing something wrong. If I go with one of the other approaches, it's a one time (or a no-time) cost and I can do it when it fits into my life. But I won't know if I'm doing something incorrectly or when I'm ready to move on to something more difficult. I would be at the whim of people who can't see me.

So, I can't decide what to do and that annoys me.