I want to create a very simple game on android (May be used to propose to my gf).

Tips for the below questions will be a great of help:
1.) What software to use in creating a simple ANDROID game that I can test right away using my phone
2.) What software to use in creating the images/sprites for the game.

Suggestions are appreciated as well.

Thanks.

It depends on how advanced you want to go and how much programming you want to do? There are services out there which allow you do make an Android app without doing any programming. I'm a opponent to such services since I believe that people need to learn how to program before they try to make any form of applications. But you can check out this site: http://www.appinventor.org

If you want to do it the "right way", at least in my opinion, you should download Eclipse for Android developers and the Android SDK and get your hands dirty with some code. It will take a lot longer to create it this way, but in the long run you will get much more benefits this way.

I'll leave the choice up to you.