I know it must have been suggested already but I’m gonna say the Pokemon series.
On a more unusual note have you ever considered the Police Quest series?

Another great monthly podcast! I took my 7 year old son to the NVM last summer and he loved it. He’s a massive Mario fan and found Mario paint so much fun. He wouldn’t stop talking about so I had to dig out my old SNES and track down a copy of the game. What they are doing at NVM is great and we wil...