Unobtrusive

When my custom-built PC finally fried its old top-of-the-line MOBO, I looked a round and tried a new quad core with Vista.  Need I say more?
Two machine returns later, my son and I both noticed that you can run Windows XP on Leopard.  So we made the plunge, and after an absence of 25 years, returned to Apple in Feb 08.
Love the quiet, and the small footprint.  Don't like the undersized HD and the slower processors.  Then I discovered my biggest dislike:  Didn't know Apple has gone away from user-upgradability.  Discovered that when I went to increase the memory and found that MY just opening the case would void the warranty. 
I got my son an Apple Logic program for the garage band modules only to find that you have to load the entire thing, and if you've partitioned the HD so you can run Windows, you won't have room in the HD to load the program.  So now I'm stuck with buying as large a notebook HD as can fit in the case (you have to make sure it's no bigger than .93cm tall or it won't fit).  And then I have to pay an Apple certified tech to put it in.
When we finally get it up to speed, I'm sure things will be just fine, but it's taken forever to get this thing working right.  I've had to take my machine back to the techs twice, and had to have the HD wiped and reloaded once.  First mouse (a separate purchase) quit working and was replaced for free.  That one started working jerkily, and I gave up and connected an old MS Explorer, which can't be reconfigured because you're limitetd to Apple's idea of what a mouse should do. 
I've already added a 320gig HD in a matching case and can backup the entire primary drive to that one using Time machine.  
Really like the wireless capabilities.  Had a borrowed PC laptop surfing the net from my living room as soon as I opened it up.  The range is pretty good; it picks up my neighbors networks three doors down, and the restaurant across the creek. 

My son loves the machine and will probably be a Mac user from here on out. 
I don't love the machine as I find apple OS incomprehensible to use, inflexible, and cannot get the mac based MS programs to work for this power user like she's used to.  (hence the need to partition and use PC versions) 
I'll be getting myself a cheap upgradable WiFi laptop with XP so I can quit fighting the computer and accomplish something.  This from someone who had an Apple in her home in 1979!