Go old school, really old school.
Go for the first ever home video game system the Maganavox Odessey but I doubt you would be able to even play it on a modern HDTV. It had plastic sheets that used to cling to the TV screen. These things would have pictures on them and block out the rest of the screen and that's part of how you played the game. I had one of these growing up and it was so much fun. It started a life long love of video games.
Here's a few links about it:
http://en.wikipedia.org/wiki/Magnavox_Odyssey
http://www.pong-story.com/odyssey.htm
Everyone see gaming evolution differently but I tend to classify gaming consoles by the leap in gameplay they provided when they were released. For me, it goes something like this:
- Odessey
- Atari 2600 - Amazing coin op video games in your home
- Intellivision - Wow great graphics, many different games to play and endless hours with friends playing this console
- Sega Genesis - WOW Sonic the Hedgehog. Then Road Rash, NHL Hockey with fighting, AeroBiz, The Immortal....so many great games!!
- N64 - I think it came with SuperMario 64 and you could, for the first time in console gaming, go literally anywhere you wanted. I had never seen anything like it before.
- xBox 360 - Amazing graphics
Honorable Mentions
PS2 - Grand Theft Auto San Andres - enuf said
Wii - For changing the type of gaming but I don't like it as a pure console gaming platform. Fun for parties though.
Anyways probably more than you wanted to know but those are my pics.