You've got a lot of interesting content, which is let down a bit by the design of the site, in my opinion.

On your news content pages for example, say this one:

http://www.computernewsletter.co.uk/news/125/ARTICLE/1067/2005-07-31.html

The article is interesting, but it feels to me like the page has been bolted together, and there doesn't seem to be much of a "look and feel" to the site. Maybe that's a "brand" or something like that. Also, the adverts seem to be a lot more prominent that either your header image, or the article.

Also - times new roman for the article text makes the page look unfinished.

The left-hand javascript type menu is well done, but the problem with having transparent backgrounds means that the menu text can be hard to read if the menus open out above / in front of existing text in the background.

The left-hand javascript menu doesn't work on the Firefox browser either. The menu expands so I can see the links, but when I click them nothing happens. The links on the menu which don't open another sub menu such as "home", "news" and "computer software" work okay on firefox.

When following some of the links in Internet Explorer, there doesn't seem to be any content on a lot of the pages, e.g.

http://www.computernewsletter.co.uk/news/65/

From a basic usability point of view, it'd make sense to have your header image linking back to your homepage. And maybe it'd be worth making your header image a bit more striking - possibly - it strikes me as being a little bit bland.

On your homepage, the way you have a grey box, with (currently) a title of "Net criminals 'customise' attacks" seems to throw the page off balance. The user sees a big grey box in sea of white, and again, if you compare how Firefox and IE deal with the same view, they treat it quite differently.

Apologies if I seem to have been harsh in my feedback, but these are some initial thoughts on looking through the site.

All the best with your work

Jim