How about Botanicula?

Maybe also Costume Quest and Stacking, if reading is not an issue? (Although the text speed could be a problem sometimes.)

Right now there's a deal on action platformers on the front page. I used to play a lot of those when I was that age.

The Humongous Entertainment games are great for kids. They can play them on their own and have a blast.

LEGO games are nice, but mine like to watch and not play. They can be hard.

I can't think of the game right now, but you collect little dots of light and grow plants silhouettes to get to a final goal. My kids like that one. I think it was a PS3 game turned PC maybe?

My kids LOVE flying helicopters on Take-On Helicopters. Reviews say that it's a very hard game, but my 5-year old can take off and fly it (maybe not to where exactly he wants, but he gets it in the general direction). Landing is tough. Our normal routine is to start in the air, he flies to a golf course, and then I try to land it for him (and usually crash it :D). The one thing I don't like about it is it says "You have been killed." I wish it just said "You crashed!" and let you start over.

Crayon Physics is awesome for kids. It's simple, but hard.

I haven't tried it yet, but Incredible Machines might just be at your kids' level (my gamer kids are 3 and 5 -- though they are hardly "gamers." :D).

I would say Outlast, but finally not :-D

Joke aside, Incredipede could be nice, the gameplay is clever and entertaining.

All point & click games like Kyrandia or Deponia.

Indie like Unmechanical, Trine 1 & 2 (my nephew love those games), Lilly Looking Through, Pid, Steamworld Dig...

i played paltformers at that age too
i hated them then and i hate them now

anyway on topic !

the lego games are a godo choice but they are all getting a bit samey these days
and these days they are also fully voiced which started oddly enough with lego batman 2

good ones to try are lego star wars 1 and 2
lego marvel super heroes
and lego batman 2 is okay too

broken age. that is all. it's beautiful, funny, and most of all, very appropriate for kids.

Great suggestion, I could imagine that this would be a lot of fun to a 7 seven year old kid. It's easy to grasp but addictive and challenging enough without really being difficult. And it has robots and cowboys in it! ;)

Trine should be a good fit, too.

http://store.steampowered.com/search/?publisher=Humongous%20Entertainment

;-)

my 5 years old seems to like spelunky, flatout 2, samurai gunn (with friends), hammerwatch, trackmania and quite few besides.

Finished Botanicula with my 5 and 6 year olds. I can't recommend it highly enough. The amount of joy we got from it is worth every penny, and it's cycling around the discounted items during this sale.

Lilly Looking Through was also great while it lasted, but as a grown up, you will be infuriated and fell ripped off at the no-ending.

We're working on Tales of Monkey Island now as a family, and so far so good!

You didn't specify if your kid speak/read French or English....

If he's an English-speaker, then Torin's Passage would be a must for his age:
http://www.gog.com/game/torins_passage

Also, it would be interesting to play with him...
Wacky Wheels is playable on the same keybord with its split-screen feature:
http://www.gog.com/game/wacky_wheels
Worms 2 has an hotseat mode if I remember well:
http://www.gog.com/game/worms_2

If he wants to play solo, Superfrog HD has nice graphics:
http://www.gog.com/game/superfrog_hd

GOMO is what you need!

He's old enough for Sacrifice . Also try buying him some FPS games, those were my favorite genre at about that age. Serious Sam First Encounter would make a nice start, with Second Encounter if he likes it. UT 2004 is also great .

Sadly not available on GOG, but he might also enjoy World of Goo or Aquaria. Aquaria can be a bit challenging sometimes, I didn't beat the final boss so far, but sometimes kids are better at this. It seems Aquaria is English only though (not sure about subtitles), so that could be a problem in case his native tongue is French.

There's also the Rayman games here on GOG, Rayman Origins you could even play together, although I'd suggest using gamepads, if you have some.