I can't really pick just one console to go back and explore, since I have played something on all the consoles, that matter at least, but I would like to go back to a certain generation of consoles, and that would be the Playstation/Nintendo 64 generation. The PSX/N64 generation took place when I was in high school, and mainly concerned with getting a football scholarship and trying to get laid, so reading gaming magazines and following the industry was the least of my concern. I did own a Playstation, but only owned 4 games: Twisted Metal 2, Final Fanstasy 7, Tekken 3, and NBA Shootout '97. After my sophomore year, my 18 year old TV decided it didn't want to work with my Playstation, so I only got to play games at friends' house or the Teen Center, on the base I lived on. The only N64 games that I really played were Goldeneye and Smash Bros., but when all the middle school kids started coming in and complaining that we wouldn't let them play with us, I pretty much stopped all together. There were other games, on both consoles, that I played for about a week and stopped, but the only games that I spent any significant time playing, or that stuck out to me were Twisted Metal 2, Tekken 3, Final Fanstasy 7, Goldeneye, and Resident Evil 2.
I would tell people to wait for the rurmored PS3 drop coming this fall. If the price drop does happen, then people have a lot of highly anticipated games to pick from, plus the games coming out in the first few months of 2010. If the price drop doesn't happen then I still might suggest getting a PS3, if they play a lot of online multiplayer games, since the PS3 comes with a wireless adapter and its free to play online.
If someone wants a Wii, they either already have one or are going to buy one no matter what anyone says. I would only suggest 360 if they have a lot of friends to play online with.