Lake Havasu is pretty awesome but it is hot as hell during the summer.
Sonoma and Mendocino had rope swings when I was in High School but you'll need some form of water transport to get there and you'll need to know where they are. I've always assumed that all lakes had them if you knew where to look.
Might be easier to just bring your own rope.
I've never been to a lake with slides and I have no idea what a blob is. If that's the blow up island jumpy thing you might just want to bring that yourself as well. Since when is that a lake feature? Don't people bring all these things themselves?