ABC Targets Younger Viewers in Fall Lineup : Television: Last in the networks’ ratings race, ABC turns over Wednesdays to some of the most successful and highest-paid producers in TV.

Delta Burke, who left “Designing Women” in a dispute, and the creators of “Northern Exposure” have been given key roles in ABC’s 1992-93 prime-time lineup, which was announced Monday.

Burke will star in “Delta,” a new half-hour sitcom in which she plays a woman who leaves “her ne’er-do-well husband” and takes a job as a waitress in a bar while seeking fame as a country singer in Nashville.

The series is scheduled for 8 p.m. Thursdays, the time slot occupied for eight years by NBC’s departing “The Cosby Show.” If the Fox Broadcasting Co. leaves “The Simpsons” in that same time period when it announces its own fall schedule, “Delta” will go head-to-head with the successful animated series.

ABC also said that Joshua Brand and John Falsey, who have created such quality shows as “Northern Exposure,” “I’ll Fly Away” and “St. Elsewhere,” will produce a new one-hour series, “Going to Extremes,” about students who attend a medical school in the Caribbean that is seeking accreditation and respect. It will air Tuesdays at 10 p.m.

The first network to announce its schedule for next season, ABC also renewed a number of drama series that have only delivered so-so ratings: “Life Goes On,” “Civil Wars,” “Homefront” and “The Young Indiana Jones Chronicles.”

“Life Goes On,” particularly, had a strong write-in campaign from admirers of its story of a family with a son who has Down’s syndrome. The series will remain opposite CBS’ dominant “60 Minutes,” where ABC had been planning to present a weekly one-hour newsmagazine. But that show has been pushed back to January.

In announcing its seven new series--four comedies and three dramas--ABC, which was last in the network ratings race this season, also confirmed that it will be risking the biggest freshman hit of the 1991-1992 TV semester, “Home Improvement,” by switching its time and day.

After registering with a bang between “Full House” and “Roseanne” on Tuesdays at 8:30 p.m., “Home Improvement” now will move to Wednesdays at 9 p.m., following “Doogie Howser, M.D.”

ABC is, in fact, turning over Wednesdays to some of the most successful and highest-paid producers in TV in an attempt to grab the night. Two series on that evening, “Doogie Howser” and “Civil Wars,” are from Steven Bochco; “Home Improvement” is from Matt Williams, who also created “Roseanne”; and the other Wednesday shows, “The Wonder Years” and a new comedy, “Laurie Hill,” are both from Neal Marlens and Carol Black.

“Laurie Hill” is about a young woman who tries “the near impossible--balancing her roles as doctor, wife and mother.”

Meanwhile, ABC’s biggest star, “Roseanne” headliner Roseanne Arnold and her husband, Tom Arnold, have managed a major midseason deal in which he will have his own weekly sitcom following hers on Tuesdays. It is called “The Jackie Thomas Show,” and he plays an egocentric TV star who terrorizes his co-workers and the network.

Tom Arnold’s sitcom will move into the time slot that will be occupied until then by “Coach,” a steady ratings winner.

ABC series not returning from this season include “Anything but Love,” “Billy,” “Baby Talk,” “Capitol Critters,” “Good & Evil,” “Growing Pains,” MacGyver,” “Who’s the Boss?,” “Pros & Cons,” “Sibs,” “The Young Riders” and “Columbo” (although the latter will continue with occasional TV movies).

In addition to “Delta,” “Going to Extremes” and “Laurie Hill,” ABC’s new fall series are:

* “Crossroads,” a one-hour drama with Robert Urich as a lawyer who puts his career on hold to renew his relationship with his rebellious 16-year-old son as they travel the country on a motorcycle.

* “Covington Cross,” a one-hour action tale set in 14th-Century England and dealing with a knight, “his three high-spirited teen-age sons and beautiful, strong-willed daughter.” Just so viewers don’t miss the point, ABC adds: “It may be 14th-Century England, but widower Sir Thomas Gray is experiencing modern problems.”

“Hangin’ With Mr. Cooper,” a half-hour sitcom in the “Three’s Company” mode, about a pro basketball wanna-be who wasn’t good enough and now teaches at his old junior high school while living with “two gorgeous roommates.”

* “Camp Bicknell,” a tentatively titled half-hour sitcom, about a young divorced woman, her two daughters, her brother and their “nurturing household that attracts every teen-ager in the neighborhood.”

Explaining ABC’s abundantly clear strategy, Robert Iger, president of the network’s entertainment division, noted the emphasis on programs with a young slant, saying that he intends to “aggressively target this important audience segment” that is highly valued by advertisers. ABC repeatedly has said that ratings are not as important as the demographics that bring profits.

In its announcement, ABC said that Linda Lavin’s new sitcom, “Room for Two,” will return in the fall, following “Delta,” on which Burke is co-executive producer.

The network added that, in addition to “The Jackie Thomas Show,” midseason entries will include the returning “American Detective,” “FBI: The Untold Stories,” “Perfect Strangers” and “Matlock,” which it has picked up from NBC.

Inheriting the cushioned slot between “Full House” and “Roseanne” come fall will be “Hangin’ With Mr. Cooper.”

And “Going to Extremes” will get the coveted time period at the end of ABC’s powerful Tuesday schedule.

“The Young Indiana Jones Chronicles,” which debuted this season to less than spectacular ratings after misleading hype by ABC that it would be a high-action spectacle, will be paired with “Monday Night Football.” It’s a mixed blessing: In the East and Midwest, it will air before the games, ideal for young viewers, but here in the West, it will be presented at a later hour following the contests.

Here’s ABC’s night-by-night lineup for fall:

* Monday: “The Young Indiana Jones Chronicles,” “Monday Night Football.”

* Tuesday: “Full House,” “Hangin’ With Mr. Cooper,” “Roseanne,” “Coach,” “Going to Extremes.”

* Wednesday: “The Wonder Years,” “Doogie Howser, M.D.,” “Home Improvement,” “Laurie Hill,” “Civil Wars.”

* Thursday: “Delta,” “Room for Two,” “Homefront,” “PrimeTime Live.”

* Friday: “Family Matters,” “Step by Step,” “Dinosaurs,” “Camp Bicknell,” “20/20.”

* Saturday: “Covington Cross,” “Crossroads,” “The Commish.”

* Sunday: “Life Goes On,” “America’s Funniest Home Videos,” “America’s Funniest People,” “ABC Sunday Night Movie.”