Apple or PC?


I am in the market for a notebook computer to use for University. I will be using it for research, writing papers (word/excel), sometimes taking notes in class, music, some photo editing, the odd DVD on trips, and internet surfing. It must be around a 12" and under 5 pounds with good battery life. I have been reading and it's my understanding mac OS X is a more stable operating system and that it is more secure from spy-ware and virusus. They also have 128Bit enscryption I hear as well. The powerbook 12" model looks perfect for my needs but my buddy who is a computer guru says macs are only good for photo editing and I will run into compatibility issues with the mac becasue they dont use a system registry or something like that. What should I do?
slov_dream
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From the research I have done it seems OS X is safer than XP out of box. 128bit encryption, password keychains, all port entries turned off by default, software firewall, Virex.
I have an IBM Thinkpad and Mac G4 Titanium laptop, both are excellent. In addition to the above mentioned items the screen on the Mac is definitely a step up from the IBM particularly noticeable when using photoshop or similar. The battery was better on the IBM when it was new but now the older Mac's battery lasts longer. The support option on the Mac is also excellent. I could live with either machine.

I also have a cheapo dell laptop at work and the screen, keyboard, battery, and ergonomics are no comparison to either the Mac or IBM.
I've been digitally retouching and enhancing famous women's faces and boobs in LA for the last eight years on all sorts of Macs. If it weren't for Apple, I wouldn't be able to afford Audiogon.