Hiya! I live right here in Philly, about 3 blocks from the stadium. South Street is fun to poke around there, its like a mini-greenwich village. Definitly very Colorful people there to people watch! There is a great restaurant down at the end of South Street called "Pietro's Coal Oven Pizzeria". We go there a few times a month. Mostly South Street is bars, restaurants, flower shops, jewerly shops and porn shops!
Old City is a great area to walk around as well. Check out Bleu Martini, great little bar up there. You could also walk around market street and check out the Independence Visitors Center, they have all the tickets to the tourist attractions. You could do a horse and buggy ride there that will give you a nice little tour of the city. Another fun thing to do is wander around the 9th street Italian Market. Go have breakfast at Sabrina's cafe and get some coffee at the Italian Coffee House, or stop by for water ice. There are soooo many more things to do in Philly. PM me if you would like any other info.