I'd have to say it's a tie between 4 game series. Sonic, Zelda,  Halo, and Mortal Kombat. I've beaten Every game. My favorites out of the series would probably be, Sonic 3, Ocarina of Time, Reach(Cant wait for 4 o come out ), and UMK. I've played them a lot.

Well, I don't have a answer to that. I am really fond of Sonic games though. But anyways, here is a list just to name a few.
Mario : Mario Party 1, 2, 3, 5, 6, and 7. (I don't know about 9 though, it might be in here.)
sonic : Sonic Adventure 1&2,
Link: Legend Of Zelda: Ocarina Of Time
pokemon : Original Red&Blue
Earthbound/Mother: Mother(Original Name) or Earthbound Zero
But there is a lot more games I love than just this.

HANDS DOWN, SONIC 3 & KNUCKLES!!!!

Well my favourite video game is actually a series and not one installment.
I'd have to say it is :

Dynasty Warriors : A beat 'em all game! It isn't very popular due to its "repetitive nature" but I enjoy it since I'm a history freak and you just feel badass defeating thousands and thousands of enemies.
The best game of the series is either Dynasty Warriors 3 or 7.

Super Mario Sixty-Four - Double Screen is my favorite video game. The company that has created this video game is Nintendo. Super Mario Sixty-Four - Double Screen has been created for the Nintendo Double Screen system.

It's a tie between a lot of games: Skyrim, Battlefield 3,Halo series (Can't wait for Halo 4), assassin's creed series, and Ghost Recon Future Soldier.

I would have to agree with what a fellow poster said, The Legend of Zelda : Ocarina of Time is my favorite game of ALL Time. In my opinion it would have to be the greatest game of all time (again, in my very own opinion.) No offence to others who would prefer such simpler games to more complicated games, this game certainly puts a great ribbon on it's package, but the package itself is absolutely Thrilling. The very reason I got into video games was because of this title, mostly. All I am trying to say in this short post, is that this game was the greatest game I ever played, and I enjoy turning on the old N64 every now and again and just playing some good old fashion Zelda. Thanks for reading.       -Venom

My favorite game is super metroid its not just an awesome scrolling, shooting, adventure, morph balling, space pirate and metroid killing game of friken AWSOMNESS. Its because its an awesome scrolling, shooting, adventure, morph balling, space pirate and metroid killing game of friken AWSOMNESS that is simple enoghf that anyone could play it and yes I copied all that for Viz just like these words right now.

Currently I can honestly say Ultimate Marvel vs. Capcom 3 for PS3 is my favorite game because it's one of the four games I own and play obsessively! I can easily beat every difficulty from easy to very hard, so I play online. It's fun playing with other advanced players.

Pokemon! Best Game every Created! (shows stunk)!!!

Sonic generations for many reasons

1. Alone,I'd come back to listen to the sound track as I ran through the stages, the music rocked!

2.Its was a good opportunity to get back to my roots with classic sonic 2d side scrolling

3.They had a good line up of stages (city escape being my favorite,since I also loved sonic adventure 2)

4.A new adventure,and me being a sonic fan,I said why not and gave it a try. I'm sure glad I did

Though I know sonic generations was kind of short,and the story was a bit shallow,I still enjoyed it. I wish you could have been able to see everyone from the past that had a form,such as tails, knuckles, and Amy. Re playability is really low,since the only to come back to is collectibles that you unlock by collecting red rings and completing challenges over the same stages again. They tried to make the game last a bit longer by making you do some of the challenges,but I still managed to beat the story in a single day.

Overall,I think sonic is back on track,but for now,all we can do is hope

I can't answer this question lol. I like way to many games that I really don't have a favorite. Unless I go by system. For 360, Halo Reach, Halo 3, Bioshock 1 and 2, Fable 3 and Rayman Origins. For NES, I like Super Mario bros 3, Castlevania, FF3, and the Zeldas. For N64, Mario 64, The Zelda games, Starfox, Mario Party 1 2 and 3. But yeah you get my point lol. I can't just choose one game because there are way to many.

My favorite game would have to be a three way tie between , Ocarina of time , SSBB , and Pokémon Red /
Ocarina of time : Because it's an iconic classic!
SSBB : Because who WOULDNT like beating sonic up? ( No offense to sonic fans ) The only thing I don't like is the great maze.
Pokémon Red : This Game Made A lot Of People Like Video Games, Like Me!

There are many, but right off the top of my head, it would be a tie between God Of War, Final Fantasy IV, Silent Hill and Devil May Cry 3.

For me, My favorite game of all time is Super Mario Bros. 3 for NES.

It's the 1st game I've ever played in my entire life and it's a game that I always come back from time to time just for pure fun. The controls were just perfect and the level design was just amazing. I'll always remember the 1st time I've entered the giant world.

My favorite games are (mainly just rpg for now)

final fantasy 7 crisis core (PSP)
I like it because unlike other final fantasy games it not turn based and cloud is my favorite final fantasy character  well 2nd favorite compare to Zack

final fantasy 13 (360)
 I like it because the story start off with all of them as regular people until they got powers and everyone treated them like monsters but instead of chasing crystals like a few final fantasy the goal of this is unclear until you get close to the end

There more but most of them I forgot and a few I am playing now and didn't beat them yet

mother 3

This could be a tough decision between Sonic CD and Sonic 4 Episode II (both PS3).
But, I'll have to go with...

Sonic CD

SEGA had really made a good remake of the SEGA CD Classic, with soundtrack selection (Japan soundtrack my favorite), Time Attack and even play as Tails (SPOILER ALERT) when you complete the game as Sonic! This is one of the greatest games of my life, with some extras sprinkled in. You should play this(NOTE: There is a new main menu screen when you press start.).