Terminal: If you can't put up with a terminal then you don't belong on a computer, everyone should have a basic knowledge of DOS or a *nix shell.
Games: Mac OS X handles games fine if you have the hardware for it, Quake 4 in your face!
Hardware: If I ever owned a Mac desktop, I wouldn't get anything other than their best, because I agree with you...they put out some systems with hardware that the PC market has had beat for a while, good thing they made the smart move to x86 architecture. I really do hate their partnering with ATI, but then again I have an Intel MacBook (non-pro) and actually wish I'd gotten one with an ATI chipset...but then it wouldn't have been black. They need more customizable options on their laptops, I've dealt with Mac desktops and what people say about upgrading was complete BS to me, you don't throw it out and get a new one, you fold it open (amazingly the one I worked on had the sweetest case ever, folded open in a breeze, it'd be nice for LAN Parties), you pop out the old stuff and pop in the new, it's like playing with legos.
Stability: Stable is an opinion...no proprietary nor OSS operating system is truly "stable", there are exploits being found constantly.
Summary: Get good with all OSes, don't be ignorant. Learn some DOS, learn some shell, dual or tri-boot your system, don't pay big bucks for stuff that runs slow but looks cool.