How to connect laptop and desktop and share files which were using the same internet connection?

Question

laptop was connected with a wireless adsl router provided by airtel and desktop with the lan cable to the internet

Answer 1

Plug in a crossover cable into each Ethernet port. If you are running windows XP there is a Wizard that will help with it.

Answer 2

logmein is remote access and desktop controll if you sign up you get trial version which lets you transfer files from 1 computer to the other and controll either 1 wirelessly  

           www.logmein.com

Answer 3

It both computers are sharing the same Internet connection, simply enable Windows File-Sharing on both computers.

See the links below for the detailed steps on how to do this.