If it's a dynasty/keeper, I'd go with Bradshaw easily. Jacobs is in the final year of his contract, and I believe Ward signed a 1 yr. deal as well, so Bradshaw could very well be the starter soon. For '08, I think Ward would get slightly more carries than Bradshaw if Jacobs went down (assuming Ward can stay healthy himself).
14 Teams, each keep 14 players
QB: P. Manning, Schaub
RB: MJD, Westy, C. Johnson, A. Bradshaw, J. Ringer
WR: TO, Driver, J. Gage, Crabtree, J. Morgan, K. Curtis, E. Bennett, M. Sims-Walker
TE: Witten, M. Lewis
K: Gostkowski, J. Brown
D/ST: Tenn, NE