In reply to Csimp1:
Based on past years, I think it's unlikely you'll get prime conditions in the Lakes in the Christmas holidays - though you never know.
Taking it as read that Scotland is the place to be for UK winter climbing, I live near the Lakes and I love it to bits, but I think you're more likely to get enjoyable wintry (that is: not proper winter conditions, but "wintry" conditions) days in Snowdonia than the Lakes due to the hills being higher and there being more options. For example, the North Ridge of Tryfan with just a dusting of snow a couple of weekends ago felt very atmospheric; you can happily kid yourself that it's got an "alpine" feel. There are also more and better ridges in N. Wales, if you're after ridges.
Post edited at 16:10