Right, I can comment on this as I've done most of it myself (Horseshoe Falls to Grindley Brook, and Burland to Hurleston Junction).
At Maestermyn Marina the towpath is closed. It was closed due to erosion in May 2006, and is currently being repaired. Before repairs started it was basically unusable, as the towpath was falling into the canal. You can detour from bridge 6 to the main road, then walk along the road to Frankton Junction, though this is a boring slog on roads with no pavements. The rest of the route is fine. In terms of whether it's sensible to walk that much, as long as you're reasonably fit, you should be OK. At least (apart from the detour) you won't have any hills! It might be an idea to take a small torch for the tunnels, though it's not necessary.
In terms of pubs, Ellesmere has the Red Lion (I think), which isn't exactly next to the canal, but has pretty good food.
It's generally a pretty nice, scenic walk.
Let us know how you get on.
H