Yes. Use the BT modem router to connect to the phone line. Connect the ethernet port of the BT to the WAN port of the Linksys. Check the documents to see if the LAN port is an auto-detect port - if not, you will need a special ethernet cable called a cross-over cable to connect the two. Basically, try it and see.
Set only one of he routers' DHCP servers and give both routers fixed IP addresses (e.g. 192.168.1.1 and 192.168.1.2 with dhcp addresses from 192.168.1.3).
Then set up as normal.