Any advise on whether there are any areas of the waterfront to walk along and sightsee?
Any areas "downtown" by the wharfs/Christopher Columbus park, etc. or would the esplanade be a better area? Thanks for any help!

The "Big Dig" and subsequent demolition of an elevated highway has freed up a lot of land close to Boston Harbor - the Rose Kennedy Greenway, still a work in progress and have to admit have not seen it this summer. It is designed to be just what you are looking for. It is close to much of Boston sights of interest. Depending on where you are staying, I might try this area and take detour to North End, Harbor cruise, Aquarium, Freeedom Trail - whatever is of interest to you.

The Esplanade along the Charles River is also nice, but not quite as close to anything but shopping along Newbury Street - unless there is something going on at Hatch Shell in way of entertainment. I think it goes without saying, but I will say anyway, I would not walk along Esplanade (or anywhere else in any city for that matter) late at night alone. There have been several attacks and sexual assaults along Esplanade this summer - all young women walking/running alone late at night. So take reasonable city precautions and I do not consider either area unsafe.

The Boston Harbor Hotel, about a 5 minute walk from Columbus Park, has free concerts and movies most nights of the week.

Esplanade and North End waterfront (wharves, Columbus Park) are quite different.

The Esplanade fronts the Charles River and is close to Back Bay and Beacon Hill. It has more footpaths than the North End waterfront. Lots of people jog/bike/blade on these paths, plus there is rowing/sailing on the River. There is more acreage here than North End waterfront too. Back Bay has Copley Square and Newbury Street shopping areas; Beacon Hill has Charles Street shops, State House and many other historic buildings.

North End Waterfront is along Boston Harbor. More views of larger boats/ships. Some of the wharves themselves have a few shops. The big plus here is you're closer to North End and Faneuil Hall area. North End has superior Italian dining options and F-Hall has a high concentration of shops (albeit touristy). North End has Paul Revere's House, Old North Church and in the summer, Street festivals.

The short answer...they're both great! If maximum distance/time walking along the waterfront is your #1 goal, as your post suggests I'd say Esplanade fits the bill a little better, but the other areas also should not be missed. Boston is such a walkable city, maybe you could do both!

I highly recommend walking the harbor walk from around South Station up to the north end - I always do this when I have visitors. Along the way you can stop for ice-cream, a drink, to relax, to eat, etc.

See:
http://www.bostonharborwalk.com/

Also, don't forget the added possibility of walking on one of the many gorgeous Boston Harbor Islands - George's, Spectacle, etc -

www.bostonislands.org

lots to see, and wonderful to see Boston, after your harbor walk, from the water - the city looks great from the harbor - there are many options for ferry rides and/or a tour of one or a few or touring on your own

Or you can walk the Freedom Trail - great walk- takes you all over town
you just follow a painted path on the sidewalk - restaurants along the way you can stop off at