Brawl or Mario Galaxy?
i say galaxy only because i haven't palyed Brawl.
but i'm gonna guess that most of the people here will say Brawl, even though Galaxy is a good game ;)
I would recommend Brawl, but I has reasons.
Having owned both, I can say that Brawl is definitely a better game than Galaxy IMO. On Gamecube and N64, the main Mario games drew me in way longer than the Smashes did (at least in my first playthroughs), and this time around I've gotten everything in Brawl and have like 8 stars on Galaxy.
Galaxy is of course similar to Sunshine and 64 in the sense that it's another Mario running around and getting shiny things game. But at least for me it lacks charm.
Neither game is bad and both are FUN, but Brawl will last you longer.
That all depends, both are great games.
I would recommend Galaxy if you enjoy epic space exploration and a lengthy story.
I would recommend Brawl if you have people to play with or enjoy a game with more collectables than a freakin mickey mouse collection.
If possible, though, i would get both. But If you want to get both but dont have the money for both, get Galaxy. It will last you until you get Brawl
Galaxy is fun untill you have all the stars.
Brawl can get boring when you have all the collectibles(Songs,stages,challenges,ect.)(and it will take a long time to get them)and you dont have any one to play against(The cpus are easy.)