Well, most 42-46in screens tend to be plasmas, with the exception of Sony's 40in Bravia screens. We've tested the latest 32in Sony Bravia (KDL-32D3000), which is a brilliant LCD for £1000, but we haven't seen the 40in model yet (funnily enough, there's a Sony Bravia press launch this evening, so we may get more details there).
However, screen burn isn't as big an issue as it used to be on plasmas, and our Best Buy budget 42in TV this year is the Panasonic TH-42PX70 plasma (£1200, but available for less if you shop around).
And if you're still worried about the plasma/LCD thing, take a look at Panasonic's two 37in screens, the £1000 Panasonic TH-37PX70 (plasma) and its identically-sized twin, the £1100
TH-37LZD70 (LCD).