Zoo Tycoon is awesome!!!!! I have been a huge fan of it for years and i own every single game. Though i don't play the original anymore, as it's got nothing on Zoo Tycoon 2, which i don't play as much as i used to mind. I don't really know why, though every now and again i do go on it and build an awesome zoo.
The new(ish) one for the Xbox is okay. It certainly has some awesome aspects to it that the PC version never had, but at the same time it does kinda suck. Mostly on the animal aspect, as there are hardly any animals at all really and you can't really build a decent zoo with some lions, tigers and elephants and their various sub-species for example. (I only have the version on the old Xbox 360, so i don't get quite as many animals as is one the new Xbox.) I love the randomly coloured ones that get born every so often though. Getting an Albino cub or a Melanistic one is awesome!
I've also heard of the Radical Remake and i've got all of their downloads. They are all really awesome, though they don't seem to do much anymore. But when i got sorta bored
(and dying to get more stuff) with their MODs i downloaded a ton more from various sites and now my game struggles to run when i build a large zoo, which is a bit of a pain. And i kinda fluffed up the Modding too, as now i don't know which ones suck, so i can't find them to remove them. xD But on the upside i have a ton of extra animals/buildings...etc to play with and many of the old animals have been re-skined so they look awesome.
Actually........i kinda want to go on it now.