In theory all you need to do is run an composit video cable (phono cable with yellow plugs) and an audio cable from your PC to the Ext socket on your TV. If your TV only has standard SCART sockets then you will need to get an adapter.
In reality running AV cables that far will probably result in a poor picture unless you invest in very expensive cables.
Far better to pop down to Richer Sounds and get yourself a proper DVD player. Even Argos are now selling them for around £60.