This will be a Wall of text, but I thought if you ask us to make choices someone would maybe like to hear motivation behind it instead of just lists.

If I had unlimited budget and only 10 pins to choose, I'd have to plan to have several generations of pins to cover everything. I've already trained myself to look beyond theme and hype factor and judge gameplay and rules above everything else there is.

drum roll, here it comes...

I'd have to have at least one beautiful machine that nonpinheads would get into and that would be:

1. MM or more probably MMr, even with unlimited funds I'd probably lean for a modernised 20yrs younger version.

I'd restrict to one machine pre 1986: I'd have to be

2. Centaur, Beautiful dark and badass (both in visual and contextual sense) playground and backglass, great rules, tough, 5 ball mulltiball. If I had more space I'd add Flash Gordon, Eight Ball Deluxe and Medusa, but Centaur takes the cake.

For DMD era:

3. The Shadow - it has everything, flow, rules, balanced scoring (how often do you have a machine where modes bring as much as multiball), modes, three multiballs with different rules for jackpots, player controlled diverters, battlefield toy with its own gameplay completely different from everything else and still pinball, great DSC sound, incredibly good wizard mode and I even like the movie, and there are alternate translites for those who don't. What's more to ask? Second Brian Eddy game on this list, but If I were to chose only one - this would be it, not MM.

4. Bram Stoker's Dracula - beautiful haunting fast and difficult game with great flow, beautiful package of animations and sounds, stacking multiballs, shallow rules but tough to execute and poetry of motion and zen when something clicks and you start juggling three multiballs. Staple Barry Oursler game for me.

5. Data East Tommy - great layout I don't mind it being "inspired" by Lawlor - I like his layouts and this one is nicely done, Lyman on rules, many modes that utilize whole playfield, tough game, multiball in stages with increasing difficulty and THE BEST pinball wizard mode. period. play like Tommy with blinds. This and The Shadow I think can make a person a pinball player with skills. I don't like the movie, nor songs, and I would still take this as a high priority game even before TFTC and GUNS N ROSES on gameplay and features alone.

6. Congo - flowy, great non linear gameplay with collecting diamonds, volcano shot, lower playfield, multiballs, journey through Africa, I played this with third flipper not working and I still liked it a lot. You shouldn't have a list without one Trudeau game and this is my pick.

7. Johnny Mnemonic - this would be my Gomez game pick and a fast game of choice instead of some SR pin (all the respect to SR for showing that pinball should be like this). fast flowy game just to spend few minutes and enjoy steel ball bashing through stuff at 150kmph, to prove yourself that your reflexes are not those of an old man, great flow and speed, excellent powerdown wizard mode, and SR congratulates you in the end.

8. Scared Stiff - I just have to have a Dennis Nordman game somewhere on the list. And it's Elvira. And you're about to give her multiple...jackpots. what's not to like? Great crate toy, animated backglass, flowy, simple and a bit easy game, but great to relax a bit, two wizard modes of which one is hard to get, great theme, humor, double entendres, animations and sounds.

9. Williams Indiana Jones - no need to explain here. Perfect theme.

10. White Water - again Dennis Nordman. Pin beautiful as a diorama of a canyon river with great flow, lots of ramps, great animations and sounds, instant favorite with people who don't know anything about pinball. My first pin. Irony has it, it was somewhat in a terrible flood (not playfield and electronics though), had to dismantle it to bring it out of the house and somehow I ruined DMD during that operation (it outgassed), sold it for peanuts in such state to a flipper. Regretted immediately. I'm still kicking myself in the teeth mentally for doing that. Well, mine didn't have topper, nor complete boulders, ramps were busted, but man it played good and had a such a great atmosphere.

If allowed 11th machine it would be System 11 era:

11. Whirlwind. Beautiful play and artwork. Very very close would be Funhouse. Although more beautful, I fear it would get stale because of simple rules and I am in fear of Rudy. Transporter the Rescue and Elvira and the Party Monsters are contenders also.

If only ten, System 11 would get cut from the list.

Other close contenders:

Tales of Arabian Nights - most beautiful pin I've ever seen, I only put it after the finishing line for it's bland modes, fact it's not suited for tournament play and thought that maybe I'd get bored of it and use it as an expensive ornament in the room.
The Addams Family - chose Tommy over it for not caring about either theme and Tommy seemed like a deeper game with cool wizard mode and better bang for buck.
Creature From The Black Lagoon - beautiful game, I'm turned off for fact that it is at most 2 ball multiball machine. Stupid reason.

Bite your tongue We hate commies here more than you do, we had to live under them while it's a distant fairytale boogieman to you