I'd go with the Toshiba with XP only. I'm not a big fan of Vista. Actually, I really hate it because of my experience. I bought an Acer laptop for $600 (got a heckuva deal on it), and it had Vista. It was pretty good at first, but the more I used it, the slower it got (not over a long period of time, actually...I bought the laptop in late September of this year, and had enough and installed Ubuntu in middle October). I did multiple things to speed it up, but it never could get back to how it was. All I ever used it for was browsing the net and schoolwork. I use my desktop (which I built with my own two hands) for gaming, so I never installed any games on my laptop. It's got a good processor and a good amount of HD space and ram, so it's not my system (as I have further proof, also)
Then, one day in my
differential equations class, I discovered Ubuntu Linux. Now I had tried Fedora Linux on my desktop before, and found it to be too labor intensive. However, Ubuntu represents the furture of Linux. Very user friendly, and can be customized to look as fancy as any mac does. Here was the big thing for me, though. The speed was incredible. I mean lightning. Faster than my superior desktop processor with 4GB of ram and XP, and it has 2GB ram. The second after I login, I can do anything. I don't have to wait like I did for Vista (upwards of 10 minutes on bootup).
Now I know a good majority of you may have misconceptions about Linux, and given most distributions of Linux are ridiculous (Even I struggle with some things), but Ubuntu is just amazing. So amazing, in fact, that I installed it on my desktop, and the speed on it is just breathtaking. My girlfriend mainly uses the desktop to browse the net and do her schoolwork, and she has since switched to using Ubuntu (you can choose Ubuntu/XP when you bootup) for all of that. There is a version of OpenOffice (that I actually like better than the new Office). The main point is that Linux is really almost there with windows when it comes to being user friendly. I mean, it still has a few years to go, but if anyone has just a little time to tinker around and such, I'd give it a shot. It's really awesome once you get adjusted to it. I don't even boot up Vista anymore, and the only time my GF gets on Windows is to play Oblivion.
But I know that didn't really answer the question you asked, but I just wanted to get all of that out there.
As it pertains to the question, I'd go with the Toshiba simply because you are going to run XP anyways, and one of the key features of Macs is that they offer something different (along with a jacked up price for the same hardware, too). I'm not the trendiest of guys, though. I get my coffee at Weigels