Is Mafia 2 for PC unbeatable, or is it just me?

Okay, ****SPOILER ALERT**** I played through the game and it was great until i got to the part where you gotta go save Joe from the dudes, but when I got to the Mona Lisa(Restaurant) and I couldnt get the front door to open. it'd just NOT OPEN. So i Replayed the whole chapter and Got there again. Still didnt open. SOOO I did it all a third time and it worked. I got the door open. BUUUT once I got to the part after you Pay Bruno back, I just get the loading screen with Car sound effects. If I let it sit long enough then all the quotes and whatnot go away and all I have left is the Spinning record with the mafia 2 symbol in the middle It also says Loading underneath. Still hearing car Sound effect. What do I do? :C