Besides the Tizen games that are obviously created for touch screens, it gets a bit harder to find the smartphone and touchscreen friendly games from Opera widgets. I went through some of the available games and here are a best three games that I discovered.
1. Bubbles (http://widgets.opera.com/widget/10982/)
Very addictive game that also happens to work great on the new 1.2.1 version of Widget runtime. Keeps track of your high score so that you can compete against your previous best. Only annoyance is that if you change the orientation, the game resets itself. Also, the game will be shown as live icon in widget manager even though it is not playable in that mode.
2. Game FiFteen (http://widgets.opera.com/widget/27001/)
A classic mechanical puzzle game with 15 movable numbers to sort on a grid of 16 spaces. Works great on portrait mode.
3. Tic Tac Toe (http://widgets.opera.com/widget/6608/)
A clear and simple game of noughts and crosses. Works best in portrait mode.