Get Medieval madness. It's a theme for everyone. When my 8 year old sons friends come over, they are amazed by the castle and the trolls.
And so are their parents.
When my wife's friends are over they play it too.

I have owned over 40 different machines.
Medieval madness is not going anywhere.
The one pin I always wanted to own. And thanks to the remake, I could get a new one with a warranty for less than original ones sell for. Upgraded dots with optional color and a shaker too.

STTNG is a good pin. Lots to do. But a bit more maintainence than most pins.
I was lucky to get a HUO one that wasn't beat. But still had to fix a couple things. I recently traded it for a Funhouse and xenon. Sold xenon and bought Breakshot. Don't regret that decision one bit.

I owned a South park at one point. It is a fun pin. Not that deep, but a good use of the theme. But it doesn't have staying power if it's your only machine.

Personally, if I could only have one. It would be MMR.

And now that I have MMr I'm real picky with what I want to get next. Because I feel all other pins pale in comparison.