I wouldn't recommend a Segway for an elderly person, but if that's your style....go for it.
a better choice might be the Worker's Housing walking tour which takes place on July 21st...
Worker
The Manchester Historic Association also has a tour on July 14th -
MHA - Calendar of Events
If you'd rather move at your own pace, instead of a guided walking tour, then take a walk around Dorrs Pond. There are lots of trails. Another site is Lake Massabesic, with miles of marked trails for the untrained hiker.
Also, consider checking with Manchester's Parks and Recreation Dept. They frequently have events that aren't advertised.