2d Game as an Anniversary Gift (need tips)

Sorry if Blind is not the platform for this sort of thing but I wanted to make a simple side scrolling type of game for my wife. My question is, what languages/tools will help me accomplish this as quickly as possible? I'm not interested in becoming a great game developer I just want to be as efficient as possible. I was thinking it would be a browser based game since I'm assuming that's the easiest, unless an iOS game wouldn't add more complexity. As you can probably tell I have no experience with this sort of thing so any input is welcome!