You have one Meg of server space to work with, but with a little care you can get a lot of pages out of that. This keeps things clearer for you in your site maintenance, and lowercase filenames have become a URL convention that surfers now expect. You do this by inserting the following code somewhere on the front page of your website. Otherwise this code must be copied exactly. Finally, your graphics must be in .gif or .jpg format only.
Graphics are a whole 'nother can of worms.
You also can't just rename bitmap files with a .gif or .jpg extension. No, they must be processed and saved by a graphic-image program.