The weekend Nielsens are in, and lemme tell ya, they are out there. The series finale of JAG bagged keep-us-on-the-air numbers — an 8.9 rating and a 15 share. Fox won Saturday night in adults 18-49 with four episodes of — this is not a typo — Cops. And although ABC came out on top on Sunday with two episodes of Extreme Makeover: Home Edition and one of Desperate Housewives, Fox finished a strong second, boosted big-time by the return of the once-canceled Family Guy (6.3/9).