Going to buy a laptop max 750 EUROS. Need suggestions

Hi guys, thanks for any answer to this topic. I would like to buy a good laptop but my maximum price is 750 euros.

The size doesn't matter really, possibly a 17'' screen (I would like to use it for watching movies), screen resoultion whatever fits to my screen; I don't need a Full HD screen (I found that 1600x900 it's a common resolution for this screen size). 15'' Could be ok as screen if performance are really good.

This is not a desktop replacement but I need quite a powerful one, I would like to play with it (well, not heavy games, actually I'm playing league of legends so it's not a big problem), but possibly a dx 11 ready card is ok.

I'm studying game-programming so I think about PhysX support (nvidia graphic card), however I found a great laptop that doesn't have it (ATI Radeon HD 6550 1GB), how does it performs so if software emulated? A lot of people told me that nvida cards needs good cooling while ATI cards doesn't heat a lot. What about it?

Battery life should be around 2 hours, doesn't matter a lot

As I stated I need to use computer-programming software (compilers/visual studio as ide/maybe some java software like netbeans)

I use a lot of external harddrives, so 320gb should be enough but bigger hard drives are better (500gb maybe?). I don't have money for an SSD. Are there a lot of differences between 5400rpm and 7200rpm?

It doesn't matter where should I buy, but consider that I can't wait a month for fixing, maybe around 2 weeks is better. I live in Italy.

I would like to keep it for (at least) 3 years, I don't like spend money for laptops, I prefer desktops

DVD reader/writer is ok, no blu-ray support needed

I would like to avoid HP, personal reason. But suggestion about this brand too are welcomed.

6GB of RAM instead of 4 are welcomed, really.
1USB 3.0 could be nice (I don't have any 3.0 device but maybe in future...), not required.
DirectX 11 support (graphic card) it's quite necessary (game-programming...)

What I found at the moment are:
http://www.acer.it/ac/it/IT/content/model/LX.RCB02.013 (best choice maybe)
http://www.samsung.com/it/consumer/pc-peripherals-print... perfect but it's price is around 1000 euros, and I don't find any sellers
http://www.samsung.com/it/consumer/pc-peripherals-print... this looks ok but I think that the first one is better than this, am I wrong?

Thanks for help