I haven't followed TNA as much as some other members may have, especially in the last 6-7 years (at least). However, they have provided me with some great entertainment before.
Kurt Angle's debut was bad-ass.
Joe was one bad MFer at the time and Angle arriving and busting him open with a headbutt rather than say a single word was awesome. I really enjoyed their match at Genesis afterwards.
I know the Christian Coalition was seen as a terrible use of AJ Styles' talents at the time (a LOT of people hated it if I remember correctly), but I thought they did a good job proving how good Christian could be if given the opportunity and they had such good chemistry in backstage segments. They had a lot of funny promos.
I think the first TNA show I watched was when Abyss/Sting started feuding. As someone who couldn't watch WCW, this was the first time I was exposed to Sting. I was a big fan of Abyss during this.
I loved anything that the Beautiful People, the original group anyway, did.
Chet Lemon, Black Snow, and Scott Steiner. Main Event Mafia was a good stable idea, not the best execution. Sting never should have joined and the way it ended was terrible, they never got their comeuppance.
BULLY RAY. I always knew Ray could talk, thank you TNA for showing the world how good he could have been on his own.
I used to hate Jeff Hardy in WWE but when I started catching him on TNA from time to time, I actually started to like him. I think they just played to his strengths better.