Encapsulation: PPPoA (PPP over ATM).
Multiplexing: VC-MUX or VC-Based.
Modulation: Multimode or automatic. However
ADSL1 (up to 8Mb) connections: Multimode or G.DMT
ADSL2+ (up to 24Mb) connections: Multimode or ADSL2+
Enhanced Upstream (AnnexM) connections: Some routers will explicitly require AnnexM or ADSL2+/AnnexM
DNS: Obtain automatically or dynamic. This means if we change the DNS servers your service should be unaffected.
IP Address: Obtain automatically or dynamic.
MTU: This should be left on the router default unless addressing a specific problem. It should be 1500 or as close to this as the router will accept.