Image Properties.

I have been reading on this subject on other threads but I don’t know if they apply to my situation. I recently upgraded and now I am naming all my images in the “Alternate Text” box below the image. In the robots.txt file I have Allow: /image.php and Google isn’t indexing my images. Then I have a brand new product I put on here: Voltaeus Rods and when I mouse over the image it says what it should but when I check the properties it says this thumbnail_Voltaeus%20middle12325893344977d216be098.jpg

How can I make the image say what it is supposed to and will I be indexed if they are correct? Thank you deeply for your help, I truly appreciate it.