depends on which part of Dallas you'll be in. West part (Ft. Worth-ish), hit Z-Boaz. East part, hit Rockwall. South part, hit Cedar Hill (36 holes). Northeast, maybe hit Towne Lake in McKinney. NorthWest, try Lake Park in Lewisville. We have a ton of great courses... what's the approximate address of where you're staying?
Good list, but as BaldGuy states, it really depend on where you're staying. It's easy to spend all day driving with a metroplex as large as ours. To add to the list; Near DFW Airport check out Arlington's Veteran's Park. South Fort Worth check out Crowley's Bicentennial Park. Those are our best 7 courses IMHO.