I would say if your son is starting to get into playing video games and you are wanting him to start on the classics then go for something like the Game Boy Color (still pretty easy to collect for) or the SNES, NES. Personally, I don't a young kid is going to enjoy anything that is older than the NES. I can't get into older games myself, so I really don't think a young child will enjoy them. I also think it will be nice to get one of the system that you have owned so you can share memories of your childhood while play games with your son. Not only are there a lot of great classics on those systems, there are also some games that still hold up well today, where I think the older systems can tend to be a bit on the boring side, especially for a kid that is growing up with games that are as detailed as games are now.

It really all boils down to what you want to collect the most and feel you will get the most enjoyment out of. I just know from my own experience that I would want to start collect the systems I'm most interested in and/or owned when I was younger before going back further.

Like 1NintendoFan I don't thinks many younger kids will enjoy anything before NES, particularly since the difficulty of some games can be truly punishing. I still have my NES from 1989 and a select few titles that I truly enjoyed and hope to pass along down the road.

I think that it would be most prudent to lean towards and SNES or N64 since they had some decent graphics and a fair amount of kid friendly titles.

I have every system (except for a Jaguar) from the Atari 2600 on...I'd start there.

Know your roots!

I think SNES is a great starting point, because many SNES titles like Super Mario World, Zelda:LttP, DKC, etc. have a "timeless" quality to them, and many games really highlight the pinnacle of 2D gaming, with colorful graphics, detailed spritework and animation, multiple parallax scrolling, etc. Also, the SNES had a great sound chip too. Additionally, you can "supplement" your future Gameboy collection by picking up a Super Gameplayer (which are relatively cheap) so he can play games on the big screen--and again, I'm recommend games like Super Mario Land 2 or Zelda: Link's Awakening that still look and play great today, despite the monochrome colors. He can also go back and play Super Mario Bros 1-3 on Super Mario All-Stars (if you don't already own it for Wii or VC).

There are some great "know your roots" games on the NES and earlier, but I think for a kid, these may be little more than a novelty. Cultivate his interest in the 16-bit era titles onwards, then show him where it all started.

Just my 2 cents. Good luck!

My first system was a sega master system in 2nd grade. Afterburner, shinobi,psycho fox, golden axe, double dragon, rtype

http://www.youtube.com/watch?v=CmMCmZkXrMQ

all of those systems are very attainable....but watch out for the NES. Prices have been slowly rising.

I would also add N64 to that list. It could be another retro system to ease your kid in to retro gaming.

The Atari. Nuff' said.

Loved it as a kid and it's still fun. My 5-year-old nephew, obsessed with the Wii, gave it a shot and liked it.

First video game system I ever played on, and I still play it today - it's certainly less aggravating than some NES games...I'm looking at *you* TMNT.

I would have to agree with getting a 2600. The setup is as simple as you can get and there are some two player games you can play with him:
Combat
Frogs and flies
Asteroids
Space Invaders
Frogger
Seaquest
Fishing derby
Centipede

The list could go on for awhile.

Thanks everyone. I am enjoying the feedback. I have a bead on a Saturn and that may last me until after I go on vacation in a couple of weeks.

I completely forgot about the N64 and Sega Master System. I also forgot that I had a Lynx as well. Looks like my next hunt may be the SNES or N64 after that. My son loves Mario games.

get another ps2. games are everywhere and cheap.
PS1, N64, SNES and NES are gonna be a hard pill to swallow without some nostalgia.

Saturn baby - best system ever if you get it to the point where you can play both US and Japanese games.

It's not a true collection until you own a Neo Geo AES system.

Ah to be young and single

If you want something to collect I would recommend the NEO GEO AES not the MVS, but know this you need deep pockets.

I have PS3, PS2(don't have PS1 because PS3 and PS2 can play the PS1 games. I have a 360 but not the xbox(I hate the old controllers. I have Wii, gamecube, SNES. I also have a Sega Genesis. Handheldwise, I have Vita, PSP, 3DS. Besides these systems I have had a an Atari 2600, Pong, a C64, (32x, segacd) expansions, dreamcast, xbox, PS1, NES, N64. Handhelds I've had gamegear, gameboy advance and original DS. I've had huge interests in having a Jaguar, Intellivision, Collecovision and 3DO.

Here's a shot of my AES.

Got my Saturn in but it probably will not get hooked up until next week. Just missed getting a Turbo Grafx. The Neo Geo will be on the end of my quest unless something falls into my lap.

That said, going to have the wife and her friend up the street search garage sales for me this summer. Maybe I'll score something good on the cheap.