Here is a list of all the games that I used to finish the game really easily. It is full of alot of rentals that you can either turbo one of the unused buttons or hit start to continue the time.
If the timer stops counting be assured that it will still count for the gold. There is a timer at the top left of the screen that will tell you how long you have been playing for. You can verify how long each game will take here:
http://www.tinyurl.com/GameRoomMedalChartmedals earned
Activision decathalon- O/G/G RENTAL
Astrosmash B/S/O RENTAL
Battlantis S/B/G OWNED
Breakout 2600- O/G/O RENTAL
City Bomber- G/G/G OWNED
Cosmic Commuter O/G/G RENTAL
Crackpots- B/S/G OWNED
Crystal Castles- G/G/G OWNED
Delta Twin Bee- S/G/G OWNED
Dolphin O/G/S RENTAL
Flak Attack- S/S/G OWNED
Food Fight- S/G/G OWNED
H.E.R.O. B/G/G OWNED
Jackal G/G/G OWNED
Keystone Kapers B/S/G OWNED
Kabobber B/G/G OWNED
Laser Blast G/G/G OWNED
Missing in Action B/G/G OWNED
Night Stalker O/G/S RENTAL
Pinball B/G/G RENTAL
Pooyan G/S/B OWNED
Rack 'Em Up S/G/B OWNED
Radar Lock O/G/G RENTAL
River Raid O/G/G RENTAL
River Raid 2 O/G/G RENTAL
Shao-Lins Road S/G/G OWNED
Shark Shark G/G/G OWNED
Super Breakout Arcade O/G/G RENTAL
Super Breakout 2600 O/G/G RENTAL
Thunder Castle G/G/G OWNED
Tutanhkam O/G/G RENTAL
Video Chess G Time Spender OWNED
Yar's Revenge O/S/O RENTAL
Video Pinball B/G/G RENTAL
Yie Ar kuhg-Fu G/G/G OWNED