I'm a professional computer geek and following is my professional opinion. If you decide to go PC then consider Toshiba for a laptop and Dell XPS for desktop. Second choice would be Lenovo (IBM) laptop and Dell XPS desktop. NOTE: if you decide to buy new laptop make sure you are buying one with "Solid State Drive" or as you might see them called SSD hard drive. A couple extra bucks goes very very far.
Interesting topic. I am a computer guy my profession but I'll speak from my personal computer use at home. I have been a Windows machine user/owner since 1987 . . . What? Yea Windows was not in existence then, so it was DOS. I think Windows Version 1 was out as a character based product and was pretty much useless. I have always had a like/hate relationship with Windows and have used them all from 3.1 up to Win 7.
The people above with laptops . . . you can plug in an external monitor and keyboard/mouse and turn them into "desktop" type machines. I have a docking station for my work laptop, that I put it in, and then I use a regular desktop monitor/keyboard/mouse.
I looked real hard at Linux. But I can't bring myself to adopt it as my primary home operating system. I don't want another hobby. I don't get enough flies tied the way it is now. I do run a Linux virtual machine for remote access to the home systems but that's another topic.
6 weeks ago I bought my first Mac, a Macbook Pro. I love it and it is going to be my primary personal machine. I'll use Macs at home from now on. I am finding it better than Windows. How? There are lots of little things that Apple has done right, that Windows and the other hardware makers can't seem to figure out. One example is the multi-touch trackpad concept. Why did someone not come up with this long ago? . . . It's insanely nice and makes my Windows laptop trackpad seem like it's 100 years old.
Anyways, I am a recently converted Mac user and would recommend Mac to anyone at this point.
I've been a programmer for over... well a long time. The first machine I programmed took up a whole room. I have several Intel based PCs, a Mac Mini, an iPad, and an iPhone. I develop applications using Visual Studio and C# (among other tools). If you want an easy to use machine that will connect to other devices, self-configure and maintain itself then I recommend an Intel PC running Windows. Download the security essentials and turn on automatic updates. Don't get angry if you eight year old printer fails to work. The life expectancy of this stuff is about three years. Now, if you are in to graphics and you want a powerful graphics or video editing system go with Apple. Or, as in my case, you want to program MAC OSX or iPad or iPhone you will have to use a MAC.
Each system has its strengths and weaknesses. It depends on what you want to do. Productivity, Windows. Graphics and music, Apple.