I need to know which wire goes on which screw in the box outside and in the phone jack in the house. Wires are red,green,black&yellow. 2 of the wires were cut in the outside box & 2 wires pulled loose in the jack.

Usually red and green(line 1), or yellow and black, then which ever is connected to 2 terminals outside, then it will connect to the red and green inside, to wire for 2 lines, connect to yellow and black on phone jack.
The terminals should have about 48 volts DC on it(unless ringing about 90 vac)
While at 48 vdc, connect the red to the negative voltage, and green to positive. You would need a Meter to determine if correct. Radio shack and others have a polarity tester($5?), if you plug it in and it is reverse polarity, then swap the wires. Should now test OK.

Radio Shack dropped the polarity tester the last time I was in there.

Then this does a little more, and is $15 and includes shipping:
New Triplett Line Bug 4 Phone / LAN Line Tester - eBay (item 220285665600 end time Oct-24-08 10:35:21 PDT)
As of this posting, they have 24 available, and also test LAN.