The Express Editions do not contain this feature (Class Designer) on purpose as it's something you get when you buy the Standard Edition or better. See this for a feature comparison:
http://msdn.microsoft.com/vstudio/products/compare/default.aspx
OK, it is now clear that the Express Editions really are for newbies, not for experienced people wishing to explore the new features that are available in VS2005.
Given the pricing for the full VS Team Suite (over £7,000!) I will be sticking to VS2003. The other alternative is Linux/Gnu...
Well, I don't work for Microsoft in any capacity but I find Express Editions (currently free for the next year ... then no more than 99 USD I believe after that) to be robust. If I wanted to use the class features I wouldn't shy from spending the additional money if the value was there. It's not 7,000 GBP to get the class features as you get the Class features in the Standard edition which retails for a couple hundred USD. You could also upgrade your existing Visual Studio for much less I'm sure.
Like anything in life, you get what you pay for. I can't fault any company for charging for a product they've spent hundreds of millions of dollars creating.
Linux/GNU is great for certain things and it may be a better route for your needs, but if you're targeting windows desktop users or want a truly robust Web Applications framework .Net is the place to go. Currently Ruby, Struts, JSF and Lamp are nowhere near as intuitive, but that's just my opinion.
I'vebeen using MS development tools from their first C compiler (release 3, if I remember rightly...) Up to (and including) the first release of the integrated Visual Studio the prices were reasonable and competitive. I also used to subscribe to MSDN, in the days when that was also affordable.
What I want is a package that allows me to handle a complete product development life cycle. This is the Enterprise Suite version. The web site assures me this is £7,300 plus. Obviously I can get versions that leave out elements, or are crippled (look at what you don't get in the Express editions).
As a manager I could probably get away with documentation (ie an MSDN Library subscription) since I have the experience to set up development processes. But as a long-time developer I want to get my hands on the product and look at how I can best use it. Microsoft have priced this product too high for my pocket; the Express Editions leave out so much they are pointless for such an evaluation. I cannot commit so much money for so many bells and whistles when I can't hear any tunes in advance. And if this version costs this much, how much is VS 2007 (or 2017?) going to cost? Why are the analysis tools not available as a separate product? Ditto the team manaagement tools? These I could adapt and use within my development processes; why do I have to give everything to people who do markedly different tasks?
In terms of 'you get what you pay for', MS are not offering indidual products - thay are offering only the full monty or the crippled midgets. I want what I want, not what MS are dumping in the kitchen sink. I do not have the option to pay for what I want - only for what MS decide to bundle, at their price. I don't even have any problems with paying for development - but I do demand the right not to have to pay for what I don't want or need to use. So I will remain with VS 2003 for the forseeable future (probably until MS change .NET so that it doesn't work with VS 2003 any more, at which time I will reconsider the broader supply possibilities). Personally, I expect MS would sell significantly more if they dropped their prices drastically, but they probably get a higher profit markup on the currenty reduced sales.
Looking at what is in VS 2005 EE, I get the strange feeling of deja vu - what else had creeping featuritis by integrating separate products and with an increasing price tag? Win-something or other, was it? I get the impression Vista is going the same route...
If you wanted to have a look at what you get you can always look at the trial version for 180 days, this should allow you to see if it is what you want.
With staying with VS2003 untill MS changed the Framework.... they have this is why they have released VS2005 so that people can develop in the .Net framework 2.0.
If you have a look at the product line overview you will see that you can have in between packages. http://msdn.microsoft.com/vstudio/products/compare/default.aspx