Get the 42 kuro.
I spent 2 months comparing sets, espec the kuro and pana PZ 42. Even though the PZ was 1080p, the kuro looked better in HD up close and far away. And i mean FAR superior. THis is with blu rays (starship troopers, stealth, kingdom of heaven) and when i took my PS3 into 'named department store' to try out some games.
Don't forget that the OP will hardly ever be watching HD stuff. If this is the case, do you really think that its worth paying £1500 for a Kuro over a £700 Samsung?
Makes the 1080p toshiba X3030 i chose for my rents last year look positively carp. il get some pics up for ya tonight oir tomorrow.
Not fair. You are comparing one of the best plasma screens ever to be released, with an LCD. You cant expect any LCD TV to compete with a good plasma, let alone the Kuro.

You should never have bought an LCD for your parents, given that plasmas at the same price point, offer superior image quality, especially when it comes to SD material.
But to be honest why spend £800 on something like a samsung when the 42 panasonic pz is much better and can be had for £900-999 from 'certain department store' that also offers you 5yr warranty.
The Samsung that I posted at the started of this thread can be had for less than £700.
Secondly, the OP will be watching mostly SD material (I presume Sky/Freeview). In time, he may start watching more HD materal, at which point he can buy another TV that will be heaps better than anything out on the market in 2008.
People seem to recommend a lot of TVs based on their own viewing habits. They discount the fact that not everybody has access to HD material and are perfectly happy watching SD-DVDs and SD SKY/Freeview.