I think I only need two inputs for now? My understanding of the USB Turntable is that it will be plugged into my PC and then the PC will play the audio out to the AMP adn the amp will play the sound into the speakers, correct?
E.G Turntable -> Through The USB to the PC -> Out The Pc To The Amp -> To the Speakers -> To My Ears (as long as there is sufficent volume ;D)
correct ???
Nope, the turntable will be connected directly to the amp. So you'll be able to listen to records without the PC being turned on. There'll be a different cable to connect the PC to the turntable, which you'll only need to do when you want to convert your records into mp3s, or whatever. (You
will probably be able to listen to it in the way you describe, ie turntable -> pc -> amp, if for some reason you really want to do it that way ;)
Also.
Unless I'm terribly mistaken (and quite possibly I am ;D). Surely if I plug a DVD player or PS2 into the TV, the connection from the TV to the amp would suffice? Or do I need a direct connection for each to the amp, rather than to the TV and then to the AMP?
It would suffice, yes. The advantage of connecting the audio directly to the amp is better sound quality (every time you pass your audio signal through a different device, it will lose some small amount of quality). So if you've got enough inputs to play with, you might as well go the direct route whenever you can. RajR's point about the audio delay for digital TV is well made, BTW.
With the PS2, it has three leads like below. 2 are for picture I think and one for audio, would it be a case of plugging the audio one into the amp?
It's one for picture and two for audio :) But, yes. That's how I have my PS2 set up at home.
Incidentally - as I said, I don't have an AV amp, but like RajR, I've heard that the Yamaha ones are better musically than the Sony ones, in that price range. I wouldn't worry too much if you've got your heart set on the Sony, though. Things such as speaker placement are just as important in terms of sorting something you're happy with.