I've never had it easier. Installation on the iMac took about 15 minutes, whereupon this gorgeous Aqua screen appeared. It's possibly euphoria on my part, but it looks sharper, certainly is a great and beautiful improvement on OS 9.1 and it makes me feel good just to look at it. Icons are now photographic rather than being little cartoons. Of course, there is a learning curve.
Stuff is in different places.
The Finder is now on the left side of the screen and it handles more than the old one did. You have the Dock where you can park anything from your whole hard disk to a movie that continues to run in its tiny thumbnail. Down to the Dock, hit the Internet button and the fog clears. Though it might have been a near thing in the early days of OS X development, when Tevanian and some of the Cupertino gurus were not thinking of keeping the Finder, the dear old thing is back with a new lease on life. It is, as Apple says, the gateway to the computer.