For a list of recommended Hardware, Please see:http://www.cyberlink.com/products/powerdvd/hardware-support_en_US.html
Refernce to laptops - Have a blu-ray player installed in both and it plays plu-ray fine. Have not connected to a 50 in HDTV. My laptops are are a 1.6 dual core and a 1.8 GHz C2D both with intergrated 128 gig Video ram.
A Low cost system can be built, I built my wife a 13-540 with a low end video card (5670, but a 5470, or 5570 with 512 Video ram should work (Equivalent AMP could be built for less). As to store bought systems, be careful. Most that have a blu-ray installed are typically more expensive. The integrated graphic in the I3-540 may work ok which means you may not have to buy a dedicated GPU. Have limited experence with AMD systems, but they are equivant and generally sligthly cheaper.