Well, I have expertise on the Red Sox.  To get from Philadelphia to Boston, try and eliminate I-95, it is always under construction and is a constant traffic jam.  Also, for a bit of the northeast feel, try driving on the Merritt Parkway, beautiful road, I really enjoy it.  Once you are in Massachusetts, do not drive into Boston!  Find a hotel on the outskirts of Boston, I suggest in the Medford/Somerville area along I-93.  It is a lot cheaper, plus it will only be a ten minute drive to Davis Square, where there is plenty of parking and an entrance onto the famous public transportation system, the "t".  This will take you right to Fenway after you switch from the red line to the green (http://mbta.com/schedules_and_maps/subway/), where you can enjoy whatever you want.  If it is your first trip to Fenway, I suggest going several, 3-4 hours, early to investigate all the different bars around the ballpark and also the small intricacies of Fenway.  It really is a treat.  I could suggest different restaurants that are my favorite in the area, but I think if you walk around on foot by the park with your friends and pick your own it might be a better experience for you.  Hope your seats aren't behind a beam!  I will let other people suggest places in Philly for you, but if nobody responds, I will speak up in another day or two.  Have fun.

The ballpark and the Holiday Inn are in a terrible location.  Get a hotel in the city and just take the subway to the game.  You'll have much more fun being in the city than being at the Holiday Inn.