I am new in .net; I would like to learn any new technology in .net. Prefer me any good technology to develop web application effectively and easily.
Well, if you're new I strongly suggest you start learning the absolute basics first: whatever language you're using, IO, collections etc. I'd then learn LINQ to Objects as a way of making in-memory collection handling more pleasant.
Then (and only then) start looking at web applications - ASP.NET MVC is very popular at the moment.
If your application is going to use a database then at some point you'll want to pick one of the myriad data access APIs - Entity Framework, LINQ to SQL, SubSonic, nHibernate, straight ADO.NET etc.
.NET has lots of different technologies.
For web development there are ASP.NET and ASP.NET MVC.
You can find more information on http://www.asp.net/
I suggest you Silverlight, MVVM pattern and RIA Services (plus Entity Framework). If you start, start learning most recent tecnologies:)