OK, pay attention, here comes the science bit:
Going For It (GFI):
Pros:- You might get what you want out of it
- You will certainly learn something (if only about yourself)
- You will gain new experiences and therefore become a more rounded person as a result
- You may discover a real talent for Law and decide to pursue it as a career
Cons:
- Cost / Time / Effort - these are all resources that you will have to expend to achive your goal. If you have these resources to spare then you can ignore this Con.
- You might not get the outcome you want
Not Going For It (NGFI):
Pros:- Cost / Time / Effort - Again, resources but this time you are saving them not expending them. Use the same logic as for Cons above.
- Safe option, you cannot fail.
Cons:
- You will never know for sure what you could have achieved, this will eat away at you and you will think about this for a long time (possibly for ever).
- You haven't given yourself the chance to be all that you can be. By not going for it you have narrowed your options, and therefore restricted yourself to only the safe options.
Summary:
GFI: Pros = 4, Cons = 2
NGFI: Pros = 2, Cons = 2
So, the Cons of the two options cancel each other out, meaning that neither option is any worse than the other (ignoring the fact that we are still factoring the resources here).
However, the Pros are at odds. The Pros of GFI outweigh the Pros of NGFI by a ratio of 2:1.
The Balance Summary therefore is: Go For It
You have to remember though, the Pros/Cons I have identified are based on my assumptions of the likely Pros/Cons for you. I don't know you, your circumstances, or your true feelings. Try conducting an honest excersize yourself (based on how I've done it above). Be totally honest with yourself though or you're wasting your time, and only include those factors which are true Pros / Cons.
Don't over think the Pros / Cons either. Just scribble them out furiously without really thinking and see what comes up, you'll probably be quite suprised.
For what it's worth (even without the stuff above), I think you should go for it. I've just decided to do an OU degree (BSC Honours, Business with Computing). It's going to take ages, but for me it will be worth it in the end.
Whatever you decide, I wish you luck and happiness.