Sometimes students enter college thinking they would like to pursue one field and find out they really didn't know what was involved. For instance, you may decide you would like to be a lawyer and are only seeing dollar signs but after you enter college/law school you discover not only is it time-consuming but it isn't as easy as you thought it would be (think of all your friends who told you that you should be a lawyer because you knew how to talk people into anything). You may also choose a field that once was growing tremendously and is now slowing down in the current economy; you begin to have fears about your financial future. And as an adult learner, it is likely you already have a decent idea of what it costs to live today.
Some students also enter college unsure what they really want to pursue, so they begin just taking some courses they know they will need no matter what degree they pursue, though it is not overly common with adult learners. The problem with taking this approach is that some students never decide and end up half way through college with nothing but the potential of a General Studies or Liberal Arts degree in their futures. While there is nothing wrong with changing your area of study, you should attempt to make that choice before you are too deeply engrossed in the pursuit of your degree. When you wait too long you run the risk of remaining in college longer in order to pick up the courses you missed while harboring your uncertainty.
Instead of rushing into making a decision, allow some time to think about the options. You may also want to take a little time before you begin college as an adult learner in order to make sure you enter the right area of study from the beginning. It takes much less time to wait a little while and make the right decision than to make a quick decision that is not the right one for you. This doesn't mean you should not enroll in college and take some courses that will allow you to develop a feel for things. After all, there are many courses that will remain the same regardless of your degree program.
Enroll in Liberal Arts and begin taking the supporting classes you need while giving yourself some space to assess what you are really interested in pursuing. When you are certain what you are interested in studying you have the option to change your area of study to the one that interests you the most. By that time many of your supporting classes will be out of the way and your can begin some serious delving and studying in your field of study.