I hope this thread isn't dead, but I just wanted to offer my input. Ultimately, if you want/need a macbook now, no matter what we say, you're gonna get it. I asked a very similar question this past december. The only difference is, it was a matter of going to college in 8 months for me, but for you, its 2 years. My advice would be that if you can easily live with whatever computer you have now, do it. Even if the macbook could last until you go to college, it won't be the newest available. Despite being able to run software, you have to keep in mind that you will be surrounded with people with the newest macs available. This isn't a huge issue, but just one that you should keep in mind (especially if you only want a mac now for the sake of having one, rather than legitimately needing one). Not saying thats where you fall, just giving you something to think about.
So to summarize, I say wait. If you don't need a new computer, wait until your senior year of highschool (at the earliest) to get it. If you do need a new computer, then buy a macbook pro. Its really up to you.