This may sound like a dumb question to those who are initiated in the ways of tv's but here goes. If I use scart leads to connect tv, dvd player, vhs player and cable reciever - do I still need rf coax's from cable reciever to video and video to tv ?
You need the coax to the video, so that you can record. You of course need the coax to the TV and the easiest way to get it is from the video. It is better if the coax conection is ignored when playing a video as the quality from SCART should be better. My experience is that it is worth paying around £25-£30 for a decent SCART and making up a coax lead using satelite cable and good quality conectors (around £2-£3). The white coax patch leads sold ready made are no good at all.
I think that I made a mistake about needing a coax from your Cable Box to your TV. Where I live I just connect the cable to my TV using coax and tune into the cable channels using my TV, but I think that your cable box does all the channel changing and has a remote. If this is the case, there is no need for a coax between your Cable receiver and your TV. My comments about coax and SCART quality still apply though.