I believe the game that got me into the Sonic fandom was Sonic Heroes, though I heard of the series way before. People hate that game for whatever reason, but I enjoyed it immensely, and I still do. And I have the PS2 version, which is apparently the shittiest one.
I played many other Sonic games on Mega Collection Plus as well.
Sonic X was one of the few TV shows I watched as a kid, but I rarely managed to catch it.