HELP URGENTLY REQUIRED!!!!!!

Hello i need to connect two lans together, each lan consists of 4 computers and all of which are connected to the internet via an adsl line, the 2 offices which i want to link are only 2 miles apart, all the computers have legal copies of windows xp pro sp2, can i just bridge them or connect the routers somehow to make life easy for once. Regards Gary Jacobs