Returns parameter value in comments doesn't display in intellisense

So I've just started using /// <summary> format comments (C#) so as to document my classes. I'm liking how professional it looks, but I'm a little confused about the <returns></returns> block.

It doesn't actually seem to put anything I type there into intellisense. If a function returns a String, I type "String" into there or DataSet if the function returns a DataSet, but it never appears.

Also, how do I get comments working with multiple lines? What I mean is how to get the Intellisense to actually print \r\n characters?