Well my darling, it looks like you have two options:
Option #1: Take it away. IF its a DS or a Wii, or whatever, just say, "it's a ___- free week!" He can come up with activities on his own w/out much help. Like read, "The Mysterious Benedict Society" with you on the bed.
You may also limit his time. I have the Time Traker that I set for my kids, and it goes from green, to yellow, to red, so they know to start wrapping things up.
Option #2: Get educational games. Math blaster, Animal Crossing, etc. Say, "Sure you can play! Just so long as its this game about the human body so that you are prepared to be a surgeon someday..."
Option #3: Play WITH him. I know, its the option that we rarely think of, but many games these days have the option for two players to synch into one game. You're on bedrest! You have some time to see what the big deal is. Borrow his games! I bet you could become a killer Mario Kart player while he's at school!
You would, in short, become the coolest mom EVER! And, you'd have something to talk about with your son - AND his friends!!! I highly recommend Animal Crossing. It's a game that gets kids into cataloging a TON of real insects/fish/dinosaur bones, cross-breeding flowers, and furniture collections. I KNOW IT SOUNDS DUMB!!! But my husband and I played it more the first year than the kids.
Are games generally a waste of time - YES! Can you manipulate it to your advantage - YES! "Sorry, no games until your room is clean/table is set/homework is done/floor is picked up - that's the rule!" And limiting time will help you feel like you are not raising a potential Pinball Wizard.
And, if you do get Animal Crossing, let me know, I'll let you come visit my town. I'll write you letters and send you coconuts to grow in your town!
Good luck - mama's are smart cookies, and we multi-task, even if it's finding common ground with our kids!