Please provide to me the information about the most famous haunted 
houses of United Kingdom country and I also want to know that what
type of experiences people observe in the above mentioned most famous
haunted  houses of United Kingdom country ??

I don't know if there is a "haunted house" considered to be the most famous.

But perhaps you'd like to read the GA Question "Brits Challenge III - ghosts":
http://answers.google.com/answers/threadview?id=433627

There is a T.V show that plays over here in the UK called "Most
Haunted". A group of investigators go to supposedly haunted
houses/buildings in the UK and try to decide whether there are any
ghosts there. You could check out their web site, and look at the
locations they've visited, and also at the sorts of paranormal
activity they claim to have experienced.
http://www.livingtv.co.uk/mosthaunted/

Definitely go to http://pages.zoom.co.uk/hauntedplaces/houseshome.htm

This will give you the perfect list of Haunted Houses in the UK. Its
all in opinion which is the most famous however they are "famous" if
thats what your looking for.