You wouldn't normally use both to connect to the television - if it is capable of outputting a signal via HDMI (which is digital and normally of higher quality and better upscaling capability than scart) then you shouldn't have to connect to the TV using scart. You may however find that your TV doesn't autoswitch to the DVD connection if you only use HDMI, or that it doesn't correctly autoswitch from 16:9 to 4:3 and back, in which case you may prefer to use scart instead of HDMI.
Either way, you will probably want to connect other things to it via scart, when recording from (say) a Sky digibox.
Hi Guys and thanks for the quick info,
i am going to fit my virgin box in the system but a bit confused by the sony hookup is thear a thread on AV already for a easy way to hook up my box is a samsung 2100c,
i am not verry good with all this stuff all help welcom