It is right next door to the 7-11 and across the street from the CVS (24/7), so very conveniently located if you need/forgot something. The walk is about 10-15 minutes, depending on how fast your group walks and when you hit the one signal before you get to the parks. The walk will keep you on the same side of Harbor as the parks the whole time, so at least you won't have to cross any major intersections. This hotel gets pretty good reviews here, especially from larger groups because of the parlor suite. Here is a fairly recent trip report with photos from a reliable DISer:
Family of 7 Goes to DLR 2/4-2/10/18.