So much is memorable, but perhaps the best stretch is from Harrows Scar to Birdoswald which has a good amount of Wall, some ten courses high. It is a great walk, and if fit, should not present a problem. It's craggy in parts, with some good views..
If you can get hold of a book called The Roman Wall, (Comprehensive History and Guide), by Frank Graham, you will have the very best book to carry with you, and it tells you what to ;look out for, and where, as well as the history.
Don't miss out the museum at Vindolanda. It's a must.
If you want more specific information, just ask.