I was on The Run Home on SEN today talking TVs with Franco and Ox. Plasma or LCD. Here's a good link, sponsored by Panasonic to get you started. There's also plenty of other great information on the web.
My advice: If you want a big (bigger than 50") screen and are into sport, go for a Plasma, for everything smaller choose LCD.
We also spoke briefly about set top boxes; The best unit for free-to-air is Tivo or if you've got Foxtel, get IQ.