What is the difference between 2 years ...

Not to sound like a smart a**, a degree.  If you only have two years of undergrad work done, my experience has been it's not going to help much, because the when interviewing the question of "why didn't you finish your degree" will come up.  For many years this was a problem for me, but fortunately my time in college was as a "returning" (ie, older) student and almost all of my course work was the mid-level and advanced courses for my major, cs.  Because the market is getting to be much more competitive, your best bet if you can swing it is to turn your two years into an Associates Degree.

From what I know of the education industry, the more education you have the better.  Depending on where you are located or wish to teach will determine what education and certifications you will need to pursue this career.  Also, what area of education do you wish to teach and do you want to work in primary or secondary education.  There is also the option of working in the private sector, many companies employ "trainers" for their staff and customers.

Basically you need to figure out what it is you wish to do with this career choice; as you can see there are many opportunities, you just need to be sure to plan according to your goals.