That HH on Samson on Penn's campus is otherwise known as "The Inn at Penn". Opened in 1999. VERY nice. Be careful during school year weekends - there are likely to be a lot of guests related to school-related events(sports, parent weekends, etc).
The Doubletree on Broad and Walnut used to be a Hilton. It's right in the center of town near lots of restaurants and culture.