I have a few walks that I tend to repeat.
In the lake district Helvellyn over Swirral and Striding Edges, very busy in summer. I have walked it in the winter (when ice axe and crampons are needed), but never seen Red Tarn frozen, which I would like to see.
In the peak district, Mam Tor & Hollins Cross then along Cave dale, and on to Limestone Way, though it can be very busy at weekends.
In North Yorshire it would have to be Malham and Malham Tarn, again this can be very busy. Though I haven't been there for a while.
Locally in the Yorkshire Wolds, Welton Dale & Elloughton Wold a great little woodland walk.