having just switched to mac after being a PC fanboy for years i would have to say i would almost never go back to a PC/windows. It has not crashed once although a few of the programs have ironically the ones made by windows for mac(msn,office, etc.).
One disadvantage to the Mac however is the lack of games that will run on it which really kept me on Windows for so long, however with the newer intel based macs you can have a seperate windows partition for this. I chose to have a 10gb partition and i run all of my games off an external hard drive. Im not really sure as to wether or not this is my imagination or not but since using windows on a mac it seems to run smoother then it ever did for me on a PC.
So in my opinion I would have to say a Mac with Tiger and windows installed on it if the best way to go and that way you end up getting the best of both worlds.
Macbook Pro:
2.33ghz core duo 2
2gb RAM
120GB HDD