In reply to Phil Payne:
Langdale or Borrowdale valleys are both good bases. Plenty of choice in both. The Langdale Spa in Elterwater is worth a look, they've done lots of upgrades in recent years and the place is looking rather fine.
The Lodore in Borrowdale also a nice place.
Or there's YHA's. The Ambleside YHA is on the shores of Windermere and an easy walk to Ambleside + ferry from the doorstep.
The Low Wood is currently a building site and looks like it will be for quite some time yet, so would be cautious about booking there for this summer.
Don't delay much longer though, it's busy up here and will get busier over the coming weeks.