Is prime time ready to take a break from reality?

The best strategy for deciphering this week’s dizzying presentations of the fall prime-time TV lineup is to follow the money -- a trail that has led the networks home again, in more ways than one.

Advertisers, in fact, have done what critics and cultural warriors couldn’t -- namely, chase the so-called reality genre into temporary retreat, leading to at least a short-term resurgence of scripted sitcoms and dramas.

Of the 39 new programs scheduled, 20 are comedies and 17 are dramas, leaving staged reality on the sidelines because many of those shows create an “environment” for commercials that makes sponsors uncomfortable. So the hours devoted to “reality” will barely exceed 10%, after stretches this spring when it occupied nearly a quarter of prime time.

“Ultimately, having a heavily reality-laden network is not great business,” ABC Television Entertainment Group Chairman Lloyd Braun said, after his network did just that this spring.

As a result, networks pounded home the importance of quality scripted programming, though even they expressed skepticism that their rivals would stick to it -- and not fill the air with “reality” -- once new shows began to fail.

“It’s what’s called the old bait and switch,” CBS Television Chairman Leslie Moonves told media buyers, referring to competitors but failing to mention the two hours a week CBS devoted to “Star Search” during the second half of this season.

Fox, with unscripted fare accounting for over a quarter of its schedule, expressed confidence that media buyers will stay on board. Fox Television Entertainment Group Chairman Sandy Grushow said the network will be “more discriminating” with the genre but added that when a mega-hit like “Joe Millionaire” emerges, “You can bet that advertisers will want to be associated with that program.”

As for creative themes, the idea of returning home, either to an actual family or a made-for-TV, non-nuclear approximation of one, clearly resonated throughout the comedy development process. Practically every variation on grown children moving home (“Happy Family,” “All About the Andersons”) or in with relatives (“Two and a Half Men,” “Whoopi,” “Hope & Faith”) is on display, as well as couples with mismatched parents or backgrounds.

Similarly, the enduring success of “CSI” and “Law & Order” in their various incarnations -- and perhaps the comfort of seeing bad guys tidily punished -- has furthered TV’s crime wave, recalling the days when westerns were prime time’s gravy train.Despite considerable discussion about the merits of stability, the promise of doing better with something new ousted many borderline series. They include NBC’s “Mister Sterling” and “Watching Ellie,” Fox’s “John Doe” and “Fastlane,” and CBS’ “Becker” and “The Agency,” with the network instead opting to keep another first-year drama, “Hack.”

In addition, 17 existing series will shift to new nights, yielding some sure-to-be closely watched matchups that include “Law & Order: Special Victims Unit” invading “NYPD Blue’s” Tuesday beat and “Joe Millionaire” squaring off with NBC’s “Fear Factor.”

At least on its face, the networks have made good on their pledge to improve minority representation, including a pair of new Fox shows featuring Hispanic leads, “The Ortegas” and “Luis,” as well as a few starring African Americans and a mix of shows with ethnically diverse casts. (“The Ortegas” is adapted from a popular British series, as is NBC’s racy new Thursday-night sitcom “Coupling.”)

The additions are such that producer Bruce Helford finds two sitcoms he produces headlined by minority comics, “Wanda at Large” and “George Lopez,” pitted against each other Fridays -- a night suddenly crowded with sitcoms and well-populated by African American characters.

As for home cooking, the number of programs networks produced for themselves dropped versus last spring, when nearly 80% of new shows came from sister studios. This year, that number fell below than 60%, or 22 of the 39 series -- which isn’t to say those time periods went to independent producers. Indeed, Warner Bros. alone has set a studio record with 28 prime-time series for fall.

Programmers have also stayed close to home geographically, with several series situated in Southern California, among them Fox’s “The O.C.” (a transplanted teen in a wealthy section of Orange County), and “Skin,” whose backdrop is the local adult-film industry.

Apparently the fate of the network’s short-lived serial “Pasadena” a few years back wasn’t a deterrent.

Going home, too, means returning to familiar stars and proven producers, whether it’s John Larroquette back in a third NBC comedy or CBS’ “The Brotherhood of Poland, N.H.,” scoring a TV hat trick for “The Practice” and “Boston Public” producer David E. Kelley, who will have shows on three networks.

Perhaps more than anything, however, the schedules are a reminder that youth -- specifically, the coveted 18 to 49 age bracket -- must be served. CBS, the most-watched network overall, is third by that measure, and rivals repeatedly pointed to median viewer age (CBS, at 52, has the oldest profile) during their presentations.

It didn’t end there. Discussing planned revisions for what will now be called “L.A. Dragnet,” producer Dick Wolf pledged that all the new characters would be “under 35.” Even CBS’ “Cold Case” -- the network’s fourth drama from film producer Jerry Bruckheimer, featuring a young woman investigating unsolved mysteries -- feels like a hipper twist on “Murder, She Wrote,” which once occupied that hour.

As Bill Morningstar, the WB’s head of ad sales, regaled advertisers with data about his network’s youth appeal (median viewer age: 31), he paused almost apologetically to say it was nothing personal, just business. “I have a mom,” he said. “She buys stuff.”