Thanks guys,
I had a look at the trout reservoirs, the trouble is the day ticket waters are kill what you catch with a minimum of 4 fish, I'm not sure quite what I'd do with 4 trout but I doubt I'd be able to eat them all! Plus, to be honest, I prefer catch and release, even for trout. So the Norton Trout Fishery looks a better bet for that, and cheaper without being too much further.
What I was really keen on was expanding my fly-fishing repertoire, the River Wandle is an excellent spot, a chalkstream in London and with plenty of Chub, Dace and even wild Brownies. It is more of a Spring/Summer location though and Colliers Wood is a long way to go from Finchley Central on a short Winter day.
When I fish Regent's I use light spinning gear, I've only fished there for a year but I've not seen a single Pike. All I catch is Perch and not of much size but still good fun, the biggest I've had from there was about 1lb and I was surprised to find one that size.
I've not fished on Hampstead Heath as I couldn't find out what species are actually in the ponds. Though again I would guess that light spinning gear would be the most suitable. What I really wanted to do was get some of the traditional Winter fish on the fly, Chub and Pike mainly. After 1st November its Rainbows only for trout fishing and their usually so deep and torpid it becomes a bit 'chuck and chance', in my experience anyway.
If anybody is interested in exploring the fly-fishing for Pike idea I'd be very happy to team up, perhaps discuss tactics over a pint? I can see that finding a suitable venue close to London might be tricky, I do have a car so I can travel a bit. I'm wondering whether the Coarse reservoirs on the Walthamstow complex might be worth a shot?