In short, the answer is very easy, if you know C # or VB. For the average website, ASP.Net is a very simple solution when used with Microsoft's Visual Studio 2008 Express Edition (VS), which is free from Microsoft. You can download it here after you signup for or use an existing Microsoft account: http://www.microsoft.com/express/download/ . The great thing about this, is that you can easily get a website up and running. VS has some great functionality, it wants you to utilize new technologies including Web 2.0 and Ajax. These enhance your website or web applications.
Additionally, if you are building a website that will be essentially the same site, VS allows you (and of course, you can do this manually via strait code as well) to create a "master page". These pages serve as a template and then your subsequent pages pull all the content from this page and allow you to place small areas of text in each of your other pages. This gives you an easy-to-use and uniform template to make sure all of your pages are easy to manipulate and also are the same as each other page.
The drawback to this, is that if you want different looking pages, this is almost useless, and makes developing a site more difficult. Additionally, .net has a drawback in that it requires either C # or VB to write any code for the site. These languages are reliably simple to master, but pose a learning curve for people that have developed in traditional asp (VB Script) or php. The silver lining, is that .net is a compiled language which protects your code. Also, the language by default utilizes preset libraries that provide a wide range of functionality you can easily integrate into your website.
If you are just starting out in web development, .net can be a great resource. The average website requires very little of the fancy tricks and tools that .net is great at integrating. Additionally, for advanced features, the languages are easy to use and the possibilities of what you can create are almost infinite.
If you like using editors such as Dreamweaver or FrontPage, Microsoft Visual Studio 2008 Express Edition is a great tool that does not take much time to master. The only thing that is difficult is mastering the master page style. Again, this creates a generic site for you to use, and by inserting "content areas" into your master page, when you create unique pages in your site, these pages are as simple as just entering in the content you want to show on the page. This provides for a simple and clean way to build, design and display a website and is highly recommended by this author.
As a website development firm, http://www.dotnetohio.com , we always try to use ASP.Net and then train our customers to use VS so that they can maintain their site themselves. Of course, we always still offer to maintain their sites for them, but utilizing VS, we can maintain their sites for less cost to our clients and less time costs for ourselves.