First time I played it was at a friend's house. I became so obsessed that I bought a copy myself, and beat most of the available scenarios. I've made several Mario-themed parks to the best I could, using many mushroom objects from the Wonderland scenery set.
Over the course of time I bought him Corkscrew Follies and Roller Coaster Tycoon 2 for his birthday and for Christmas. He copied RCT2 and gave it to me shortly afterward.
In RCT2 I completely leveled one of the available parks and saved it in a file, so I could always play around with this empty space with all the themes and rides, rather than using the scenario builder, which I felt took a lot of time to use. I once used ALL the space to my advantage, building at least 20 roller coasters with the stations high above the ground.