Bruschi54,
It's kind of tough to respond to your posts when I'm not logged on the board, don't you think?
Anyway:
Cover 2 is a zone coverage scheme for the two safeties, not a scheme for the defensive front 7. In a 4-3, your MLB might drop back in the middle to help the safeties. In a 3-4, the extra LB can rush the quarterback and you'd still have the other LBs and the corners in the zone under the safeties.
In cover 3, the strong safety and outside LB covers the flats. The OLB takes the weak side.