Anyways, that was a very good answer actually. Didnt think of anything shorter to say as usual.
lol ;)Ok.. so this is like a graphics program?
It's the industry standard html editor... generally used with photoshop, the industry standard graphics editor.
Why don't you head over to www.Macromedia.com , and download their 30 day trial version of Dreamweaver? Sort of 'try before you buy', to get a feel for what it does.
edit: link for you: http://www.macromedia.com/downloads/
Also, could I offer you one piece of advice? Well I'm going to anyway lol ;)
Instead of using a massive image and slicing it up to a million little pieces, try using a layout, either in a table from a html editor, or a proper css layout, and use html background colors to save some of your images. That really cuts down your download times, and if your layout breaks it's easier to fix.