Your website does look pretty standard, but that should not stop you selling things. What you need to do is to personallise your store. Look at your competitors sites and see what they have done. Dont copy their site, but add things that you think may help your site.
I see that you are a UK based business. For help with your privacy policy got to
http://www.businesslink.gov.uk/bdotg/action/detail?itemId=1076142085&type=RESOURCES
Once on that page you can also find terms and conditions, and much more to fill your information pages. Alter the example text to meet your needs.
To make your site look different, you can design your own style or use the contribution found at
http://addons.oscommerce.com/info/7757
Search through the contributions limiting the search to 2.3.1 and you will find many usefull add ons that may be benificial to what you need.
You could also try using html code to make your descriptions on your product pages look better. All you really need is things like <p></p> whick puts text in a paragrapg, <br></br> which starts a new line. More can be found by searching using google. The image you use look like scans taken from a magazine, you can see the staple marks, yet in the description you say they are originals and not scans. If that is the case use the actual image as the image on the page.
As you are selling images, make the product info image larger, and centre it on the page, and add the text and options below it.
What you then need to do is to personalise the site. Go through the languages pages and alter the text. This will make your site different from other oscommerce sites. Move all the boxes to the lefthand column so the page is wider. You could then make the left column wider so that the catagory box links do not go over two lines. Its things like this that will make your site that little bit different.