According to the A.C. Nielsen co., here are the top 10 shows for the week ending Dec. 8, their networks and ratings. (Each rating poing equals 970,000 homes.)1. Seinfeld

NBC, 16.9

2. ER

NBC, 16.4

3. Movie: Mrs. Santa Claus

CBS, 14.7

tie Men Behaving Badly

NBC, 14.7

5. Home Improvement

ABC, 14.4

6. Friends

NBC, 14.3

7. Barbara Walters Special

ABC, 14.2

8. Movie: Home Alone 2

Fox, 13.8

9. Monday Night Football

ABC, 13.6

10. NYPD Blue

ABC, 13.3