Did you watch this video?

http://www.dotnetnuke.com/Portals/25/Videos/TrainCert_IntroductionTo3.0.asx

It sounds like you need a hosted solution.  I use http://websecurestores.com/ but there are many others out there if you just "google" a search for something like "DotNetNuke hosting".  These companies will even install DNN for you.

To edit and add pages, you do all of that in your web browser just as that video above explains.

To change the look and page structure, you will need to use a "skin".  There are a few free ones out there that you can take and just modify them, if you want to put in the time, you can create your own skin, or you can pay a graphics company to create a skin that you can apply to your DNN portal.  You can find a "skin" developer by googling something like "DNN skins".

If you want to experiment with it before you drop the money on a hosted solution, you can set it up on your Windows XP Pro workstation, but the install takes a certain amount of technical know-how to setup.  I made a small document that shows how to set it up on a Windows 2003 server and SQL Server 2000.  You can download it by clicking on this link http://mehenson.com/Portals/0/Installing_DNN4.pdf

Good luck,

DNN is an ASP.NET web application which requires the "IIS" webserver which can only run on WinXP Pro, Win2000 Pro, Win2000 Server, and Win2003 Server.  Also, if you are going to use this in a production environment where many people are going to access it, Windows XP Pro might not be a good option because IIS in Windows XP Pro only allow up to 10 web connections at the same time, and the Server operating systems dont have a limit.

Because DNN is designed in Visual Basic .net, I dont think that your dhtml background will help much, but  your CSS knowledge can come in handy though because it does use CSS.  You will need to keep in mind that this system is completly web based and all aspects of DNN are dynamicly database driven with no static pages.  ASP and ASP.NET is server side processing which means that when a person requests a page on the server, the IIS webserver translates the programming code, pulls data from the database, and bundles it all together as a webpage that your browser can understand.  You are probably used to client side processing such as javascript which the client performs the calculations and runs the programming code at the client, but in ASP and ASP.NET, all processing is done on the server and all the client gets is a normal webpage.

If you try to "view source" on an ASP or ASP.NET web page, you will see alot of HTML, but that code is not static, it's dynamicly created by the webserver.  If you view an ASP.NET file on the server using notepad, you will see something completly different, you will see alot of Visual Basic, C#, or some other programming language.

If you plan to do web design far into the future, I recommend that you start learning these dynamic database driven technologies because more businesses are moving this way every day.  A good place to start learning basic ASP and ASP.NET is here http://www.w3schools.com/ then you can get a book, a copy of Visual Basic Express (free) and start coding websites that use a database for its content.

Good luck, and I hope that DNN turns out to be an option for you.

Windows XP home does not have the option of using the IIS webserver software capability.  Microsoft made the home version for just regular home users that will just use it for basic computer needs, if you plan to do programming, or connect to a domain, you will want to get Windows XP Pro which costs more because it gives you these added capabilities.  ASP and ASP.NET web applications can only be translated using the IIS webserver software bundled with Pro and Server operating systems.  There is one open source technology out that might work called MONO which is being developed for SuSE linux by the Novell company, but unless you plan to put in alot of testing and learning, I would just get an OS that can run IIS, or wait for your hosting company to set it up for you.

I hope this helped.