Hummm... that's a tough one, I've been playing games since the Atari and it's been a norm for me to play the hell out of anything I got at the time. I'd have to look at the Atari, Colecovision, NES and Genesis for most of the games I've played that much since back then I didn't have as much money to get games, but had lots of time to play them. Of course I can't confirm any of them, but these are the games I had a long time then and since I had a habit of playing anything I had for a bit on a regular basis. Hell, on the Atari and Coleco I'd say that at least three quarters of the games I owned got that kind of play time. (Thanks to the crash, I had a lot of them for years and had gotten few new games till a few years into the NES's life)
For the NES
Contra (I used to be able to go though that whole game without dieing at all... and to do that takes a hell of a lot of time to pull off)
Kid Icaris (Same as Contra)
Super Mario Brothers 1, 2 and 3 (The first two I had when I got the system and beat them repeatedly, then the third came out and did the same... and that don't even include the reissues)
Goonies 2 (I figured this game out without a guide... it had to had taken over 100 hours)
Legend of Zelda (same as Goonies 2, just with a lot more replays)
Genesis...
Mortal Kombat
Sonic the Hedgehog (all the main games...)
Those are the ones I'm sure of, I've probaly got tons more from back then, my time has gotten more limited in the last 10 to 15 years (and get get new games a lot more regularly) so I've not got as many games with those hours any more, but several I know of that have are
Pokemon Blue and Silver
Sonic Adventure (Dreamcast)
Grand Theft Auto 3 (Loved to just pop in and just keep respawning weapons as I single handedly held off a 5 star police force, never finished it, or any GTA game though)
Lion (a nature based PC game... the game just clicked with me and I had more then once played that one from sun up to sun down)
Dance Dance Revalution (and I still suck at it.. I just have bad rhythm)
Guitar Hero (the first I did, though let's face it, later games are just more songs and instruments, and like DDR, I still kind of suck)
Beautiful Katamari (got the 100 hour achievement, might have played as much in the first game too)