Hi Savanna
You can see what images Google has indexed here:
http://images.google.com/images?q=site:savanna.mosaicglobe.com
While we can never be sure exactly how Google decides what images are more important than other (see article) the following tips will help:
1. Give meaningful names to your images. (GoldenAspenTrees.jpg )
2. Give long description tags to your images.
This would need to be added to your tag in HTML view.
Example: longdesc="Gold aspen tree leaves fall nature photography".
3. Larger images seem to get priority.
5. The title of the page where your image resides will also weight the images relevance.
Your HTML source code would look something like this: