Without going into to much detail, i worked for a compression and authoring facility that did Blu-ray compatibility, and tested various studios discs on just about every brand of player from profile 1.0, 1.1 and 2.0.
If you want to actually be able to watch every movie you buy/rent, the PS3 is the way to go. I also liked the Sony stand alone players S350/S360, or even the S550's. If i recall they all use the pretty much the same chipset.
If you can bare the loading times Panasonic also makes a quality stand alone player, the BD50/BD60/BD80 are all comparable.
The LG players were OK, but had trouble with some studios titles and would often crash randomly.
Though if you'd like to Spend $500 you could buy an Oppo BD83.
They were quality as well.
If you'd like to never watch a Blu-ray movie you can get a Samsung player, all of their models were equally shitty.
To answer you 2.0 BD-live question, i never saw anything come through our place from any studio that interested me in the least related to BD-Live.
Also be aware that a 1.0 player will not play most of the interactive features of a disc. (for example discs that have a PIP stream)
In buying a player, you can be concerned with build quality and SD up-scaling, but to be honest some players will play every Blu-ray disc out there, and some of them just won't play certain studios titles.