Board Thread:General Discussion/@comment-2055856-20161109191319/@comment-1031724-20161129013438

I'd say Sonic Adventure, coz it's got a fun story and good soundtrack, though playing as Knuckles and Big can be annoying due to having to seek the Emeralds as Knuckles and go fishing for Froggy as Big

The best sidescrolling one would be Sonic the Hedgehog 2, it's not overly difficult like the first one, Tails is in it, and it's got some cool levels to them (exception being Metropolis which is full of annoying enemies)