In reply to marelibertas:
I think there might be some confusion here.
Falling into a pool/river in the Lakes in October would be an incredibly bad experience. Falling onto a bouldering mat however, would be OK, and is what most people would choose.
By far the best bouldering in the Lakes is by the sea at St Bees - it's probably the best easy-mid grade bouldering in the UK. Amazing sandstone, lots to go at, beautiful setting:
http://www.ukclimbing.com/articles/page.php?id=5858
Carrock fell is OK too. The rest is a bit shit if you ask me.