Hi Dirk.
I have been a PC user for about 5 years and had never considered a Mac. They were always that outsider that wanted to do things different (so I thought) and almost resented their existence. I was a Windows fan and didn't know anything different.
I bought a G3-400 Notebook because I could get one at a good price from a friend...no other reason. I was hesitant but felt refuge in the fact that I could run 98 using the program "Virtual PC" which "Emulates" the windows environment by reconfiguring your hardware. A similar program called SoftWindows98 does the same thing but tries to replicate your Operating Platform - far too draining on your computers memory I think. My old software wouldn't be obsolete after all. I had initially intended to run the computer as a PC.
I am a changed man. The Mac platform is user friendly, my notebook is at least 50% faster than my Desktop 600MHZ PIII and has more functions and better functionality that any PC I have ever worked with.
I use it for building high-end databases, Internet graphics, video editing and Flight Planning (of course), net access and it even stands in as a web server at times! It really is an incredible machine.
I will have to agree with Captain Pprune here. You cannot beat a Mac.
Having said that. Computer technology today is incredible. Even if you buy a crappy computer, regardless of platform, it will be more than adequate for most people.
Good Luck.