I am using LoadRunner6.5 for Load test of my application . i am testing for 1,2,5,10,25,50,100 ,,,users and i am analysing the application performance and response times.
I am explaining a scenario :

I have a login page (Login and Password fields and a Submit button) , if i do manuvally in three systems (three users open the browser in three different systems and in same time they entered the data and pressed the Submit button)
they got the result page in 2sec's . if i use the LoadRunner controller ( I created a scenario for three users for login page) , i got the response time is 4 to 5 sec's . so is Loadrunner will take some time for loadrunners memory or it will give the response time of the application only .
how can we judge the final response time , can we reduce the response time for loadrunners itself (getting executed) , if so how much percentage we can reduce it.

please help me