I like the design with the big splash image. You also make it immediately obvious who you are, what you do and what this site is for. This is great, but I have some suggestions that may make it better:
1. Your website title(the one that appears in your browser tab) is in all caps, kinda seems like your yelling.
2. Your title image could be better. The pic with the rocket launcher is not as eye catching some of your other work. Take your best picture and set that was your title image. You also have that same image for every page. It might be better if you use an image from each project. Also your page is wide enough that you could forget the thumbnails and just do larger images, so visitors would not have to click and wait for it to load, it would load as they would scroll down the page.
3. The large blank space at the bottom could be used as additional navigation. You could put thumbnails of your work so instead of clicking on projects and then a specific project, they would be right there at the bottom of the page ready for the viewer to go to the next project.
4. The descriptions of your projects could use a little refinement as well. It may be a little nitpicky, but they don't need to be a story. I want to know about your work, not how you ended up working on it. I think any description of a project you have should tell who, what, why, when, how as fast and specifically as possible, a little bit like the headlines in a paper. Just tell us what exactly this piece is, why you did it, how you made it, and what it was for. You want to grab the viewers attention quickly, so I would even go as far to say that you should put the descriptions below your thumbnails, or in the empty space to the right of them.
5. Your headings, just below your title image have such a small margin around them. It may look better if you indent the text about 5px and move it 5px down so there is a nice border around it.
6. The images in your gallery and your screen shots are aliased and look quite rough. When you take screen captures, you should have some sort of anti-aliasing on so they look smooth. Frame rate doesn't matter if you are just taking still images, so crank up the resolution and filtering so you have some shiny high rez, high detailed images to show.
You may also want to watermark them in case poeple decide to save them to their hard drive.
I know some of these are rather nitpicky, I just think that presentation is a big part of your work. If your presentation is "half assed" then it kind of implies that you don't care about your work; Like your saying "its not worth the time and effort to make it look good." You did do a great job of making it fit perfectly in a 1024x768 rez monitor which is nice.
I hope this wasn't too harsh and you found this advice useful. You may also want to look at
this. for some portfolio site formatting suggestions.
and
this for a great example of a portfolio site. He does pretty much everything right and has a top notch presentation of all his work.
Good luck and keep at it, hard work and perseverance
will pay off!