If you're willing to invest a bit more money in the machine, and probably end up with less issues and general stress when using it, then the Mac is the right decision.
A windows PC will be cheaper, and will do everything that you want (at least, what you list here), but won't be as nice in other ways.
Apple think that people may have a digital camcorder or other similar devices, and want to play with the output on their computer. So, they make all their computers capable of doing these tasks fairly well, meaning that even their cheapest computers are fairly well-speced, but it also means they're more expensive than lots of the cheaper Windows computers that are on sale now. The difference is that these cheaper ones don't have the specifications, and while are probably capable of running similar software, they won't do it as easily.
A Macbook sounds great for you though, in my opinion.