I'm looking for a laptop that can do the usual surfing, movies & connect to a big screen plasma etc. Not worried about games.
I've seen heaps at MSY but not sure on what cpu to get. It seems best to stick with a SSD for the OS these days and at least 8GB DDR3
Anything i3 or better (i5, i7) will work just fine. You will be able to play HD video without any additional video card (and even simple gaming). Even a first gen i3 will be fine.
SSDs are great, though unfortunately cheap laptops don't come with them, so you are probably better off buying a laptop without an SSD, and an SSD separately and throwing out the drive that comes with the laptop.
Also, 4GB of RAM is probably enough for you. Most applications are limited to 2GB or 4GB each anyway (depending on the application). If you are editing video, sure spring for 8GB, but for the uses you listed you probably won't notice a difference. Having said that, the cost difference shouldn't be much.
Other things you haven't mentioned are size, weight, battery life and screen resolution. All of these will have a big impact on cost.
In short: any i3/i5/i7 you like the look of will do what you want. But you probably at least want to consider what the right size is for you.