There are so many peaceful video game music out there but the one Ive been listening to recently is

By far:
Chrono Cross - Dream of the Shore Bordering Another World.

I use it as my alarm clock music to wake me up in the morning. It's the best!

Snap! I thought I would be the only one recommending dream of the site bordering another world. It's been my wake up song for years.

The Venerable Forest from Star Ocean The Second Story.

http://www.youtube.com/watch?v=yC3M8MzPZMA

Fortune Teller 2 from Tactics Ogre Let Us Cling Together

http://www.youtube.com/watch?v=dWpaLijbDoA

Quest 4 from Brigandine The Legend of Forsena

http://www.youtube.com/watch?v=L51cKCbUCZI

DKC 2

Off the top of my head I'll say Flower.

it has to be this... anyone who says otherwise is lying or deaf :o

There's some Final Fantasy tracks that are very peaceful, some from Zelda too

There was a particular track in Super Mario 3D World that was very nice too but I can't remember the name unfortunately, I think it was Puffprod Peaks or something along those lines.

But yeah, there's a bunch of games that have some good ones, like Journey, Metal Gear Solid, Super Mario 64 and so on.

The music from Flower is one that stands out especially to me, So peaceful.

Jolly Roger Bay. Apotheosis. Fairy Fountain / File Select theme. Forest of Hope (Pikmin) always gets to me. A lot of the town and environment themes in Xenoblade can qualify, especially at night.