It basically comes down to two questions:
1) What do you want to do?
2) What's your budget?

Macs may be simpler to use (although there is a learning curve), but with a PC you'll get a lot more bang for your buck. Even though I poke at MS all I can, finally, it doesn't matter what OS you operate. Using a Mac or even Linux won't save you from something nefarious. You need to follow best practices at all time, especially with keeping the system up-to-date will all the patches. Being behind a hardware firewall (viz, a router) helps too.

I personally went to Linux to get off the constant Windows upgrade treadmill and the costs associated with it. I know computers and how everything works well enough that I'm more than happy to pay with my time rather than with my cash. From a philosophical standpoint, I hate how both MS and Apple (although Apple to a far greater extent) tries to lock you in and limit what you can do with your own stuff. I also don't have a ton of free cash so I can't justify paying substantially more for the same amount of hardware power.

Practically, I'd look at software solutions on both sides to see how they would fit your needs. If everything is equal on the software side, go with a PC and save some cash. If the Mac version of the software is much easier to set up and use, go that way. It's easier to look at things from a task-oriented standpoint than an OS one. That should (in a perfect world) be irrelevant.