NES, I also had the Original Gameboy but I didn't get one until quite a bit later.
For a while, my only gameboy game was Tetris. Back than, the only way to play Tetris "Mobile" was to clunk around the large gameboy. We didn't have a downloadable one on our phones.
I didn't really care about mobile game anyway UNTIL Kirby's Dreamland 2 AND pokemon Blue - By the latter I already had the gameboy pocket. I don't remember when Kirby's Dreamland 2 came out so I might have had to use the original gameboy for that.
Of course I had Super Mario Bros 3 on the NES. First video game I played and still my favorite to this day