I've had my Macbook Pro 17 for about 5 years. I've never had a virus or had to reboot for anything other than upgrading the software. I started with a Commodore 28 and worked my way through many PC's. Then I experimented with Linux, that is what eventually got my to buy a Mac. My son DJ's and he started with PC and had a lot of crashes, we got him a Macbook pro 15" and he said he'd never go back to PC, as far as productivity goes, you can get Open Office for free, and it does everything Microsoft Office does. I actually have mine set up to save in Office format since I have to deal with Microsoft products at work. Adobe Photoshop, Coreldraw, and many other productivity suites work best and trouble free on Macs. Get as much RAM as you can afford, the newer one I think can hold 8 gig. Mine is limited to 4. My son has 8 in his. Once you go Mac you won't go back. I do have Win 7 on a desktop that my wife uses, and I converted my Win7 netbook to Ubuntu. Also Apple's customer service it great to deal with. My only issue was a battery that went out after 3 years of leaving it plugged in all the time, and the replaced it at the Apple store for free. The newer Macbooks with the solid state hard drives also have longer battery life, not as long as an Ipad, but twice as long as my Macbook. If I ever get a newer one it will be a 15" instead of 17".
17" is way to much for me! If I ever need a bigger screen I will hook it up to an external.