When you're trying to develop and iPad game what will be the differences between iPad 1 resources and iPad 2? Seen some example but what's the difference?
The displays are the same. Meaning that you'll have 1024x768 pixels on both models. So you can use the same assets on both devices. The iPad2 has a better CPU, GPU and more memory, so you can technically build more complex applications and load more resources into memory.
You can compare the exact specs on Wikipedia.