Thank you all! Well, I went to Best Buy and played with the 13" and 15". The more I thought about it and what I want to do, the 17" is out of the question. I need something easy to carry around a lot and I'm trying to avoid my normal action of spending money on things I don't need. The 13" seems to work, but it's difficult to tell in that limited time and without being able to use it on my lap, etc. So, after seeing some posts online about it and what people had recommended to them by Apple Store employees, I contacted Apple to find out their return policy, being upfront that, if the 13" didn't work, how hard would it be to return it and get a bigger one. She said that was no problem as long as it's within 14 days. No restocking fee or anything.
So, I ordered the 13" Macbook Pro. I'll give it the two weeks and see how it feels. If the screen size feels too cluttered, then I'll return it and get the 15". Mostly, I'll be using it for school, being on the internet when I don't fell like sitting at a desk, maybe a little programming and movies on the long flights (which I'll have a bit of them in the next couple years between Korea and Indiana). The only thing that worries me on that screen will be the programming, but, truthfully, I'm not sure how much I'll be doing that unless I decide to take programming classes, after all.
My last laptop was a 14" and I had no problems, whatsoever. I tend to only do one thing at a time and I don't like having a bunch of programs open. As for the battery, the only time I'll be really concerned is those long flights, but I found something for about $150 that you can plug into to give you more battery time, which will work great.
As for Office for Mac. I can get it for $10 (woohoo HUP!), so the cost is definitely worth it if it works well since, while most of the time, compatibility works well between basic documents, having the actual thing will make it easier. I found the press release from Apple about Lion being a free upgrade so I'm covered there.
To biro: Thank you! I'm greatly looking forward to it. It's my second time there and I loved it the first time. I'm only an hour from Seoul, so going to Liturgy is very easy (take the train, make one transfer and it drops me off at the bottom of the hill that the Church is at).