Check replies by me, in other threads.
I have/had both. Plasma has a much better picture, but even with current technologies MAY have burn in issues.
By chance I have 1 of the TVs you are looking at, the 4665 (46" 1080p Samsung LCD)
Also have a LG 42" bl5d 1080p, and in all honesty of the 2 TVs the LG BLOWS away the Samsung for a 3D look.
Granted, my Plasma had blown them both away, except for the burn in (which happened within 24 hours). (50" 720p samsung plasma)
For the fact you will be sitting 10 feet away from a 42" or maybe a 46", in all honesty, save your money on the 720p to 1080p debate.
If the price is right, then get the 1080p model, but the difference from that range will likely be UNNOTICABLE.
If you ask what sources i base my opinion on, they are as follows.
Toshiba HD-XA1 (1080i), Toshiba HD-A2 (1080i), PS3 (1080p), Samsung BD-P1200 (1080p) HVD-2085 (1080p)
As well direct TV HD (1080i & 720p).
Static image, by using the PS3 (or granted you did say PC hookup), you would be better with LCD.
But you may then suffer with VERY minimal motion blur, as well not as good contrast, by going LCD (but it would be safer).
My choice for the 10 foot range, and to save you a few bucks, going by the TVs I have (and had) would be the 42" LCD or just step up to the 50" plasma (usually for the same price or even cheaper).
The Panasonic 50" 75u, is currently 999.00 at Best Buy (well at least the one by me) and is known to cause the least issues with burn in.