i am doing Windows base programing using C# from last 8 months and you can put me in Level 8 in C# out of 10. Now time come to switch to Web programming and get some more ingred
this is one of those "it depends" answers.
The thing with .Net is, if you have the IDE (Visual Studio), you can develop not only ASP.Net pages, you can also pursue Forms Applications, WPF, Silverlight, Services, etc. What would matter is which programming language to use in .Net (C#, VB.Net).
I would suggest prioritize in what you want to focus. Some ASP.Net noobs I worked with focused too much on the HTML/GUI side, while there's nothing wrong mastering it, they tend to compromise basic OOP skills. You have to understand, the reason why you're using ASP.Net versus a static HTML page is you want your web pages to become "dynamic". In order to achieve that, you have to do back-end programming and not just markups and javascript. Forget about the drag-n-drop objects shown in the tutorials, if you work in a corporate/professional environment, you'll barely use those.
I started learning HTML when I was 15 (i'm now 27) and those years of experience made my HTML & Javascript coding as trivial tasks and I was able to focus more on the C# logic.
The problem though with starting of as a Windows Forms programmer is, they usually had to learn developing web sites the hard way. Some fail to understand the concepts of Page Lifecycle and the limited states that ASP.Net offer. If they're using ASP.Net Forms, they almost automatically abuse ViewState objects to achieve what they want, and abuse the ASP.Net AJAX control.
Try to find a balance between those two scenarios and you'll be alright. Good luck!