If budget suits why not go full suss? A mountain bike ignoramus but can't you just lock out the rear shock for trail sections where you don't want full suss?
Anyway back to the bikes
.
Don't know the equipment well enough to know what's good and what isn't but if you can go to the £2k mark then these look like reasonable/good deals.
[url=http://www.evanscycles.com/products/scott/genius-40-2009-mountain-bike-ec016245]Scott[/url] down from £2,600 to £2,000. I know Wal has a hardtail Scott so may be able to offer opinions on what they're like.
[url=http://www.evanscycles.com/products/lapierre/spicy-316-2009-mountain-bike-ec017804]Lapierre[/url], very nice looking bike and £300 off.
For a couple of reviews Nirvana offer...
[url=http://www.nirvanacycles.com/news_trancexreview.htm]Giant Trance X2[/url]
and
[url]Lapierre Zesty[/url]
which may give food for thought.
I'd still revert to what fits best as a first port of call for any bike though, and you can only tell that by trying them out. I think Nirvana let you test ride, don't know where but they're only round the corner from Peaslake so maybe they let you take a bike or two round Leith Hill.