If it had to be one vehicle, it would be a GMT800 Suburban, $8000 should be enough to get a 2002-2004 model with a shade under 100K. There's my 7-8-9 passenger seating and towing ability. MPG from 15-18 or so. Works for me.
For $8000 I would be more likely to buy two vehicles so I have a better choice when it comes to moving people and things.
1) $5000-$6000 for a GMT800 Suburban/Yukon XL, 00-02 model, 100-150K miles. That's the family hauler for when all 6 or more of us go somewhere together. Still gets high teens, no worse than the Durango we have now, just has more seatbelts, more cargo space, isn't about to need a transmission, etc etc etc...
2) $2000-$3000 to spend on a very clean late 80s-early 90s subcompact sedan with a small engine and a 5-speed, cold air, 5-passenger seating. This would be the family hauler when not ALL of us are going somewhere, the daily driver for grocery getting and other tasks, and basically would see 60-80% of the driving. I'm thinking 88-91 "EF" Civic, 88-92 Corolla, 89-92 Prizm, or the next generation of each (92-95 "EG" Civic, 93-97 Corolla/Prizm). Also would consider a Subaru Loyale, Mirage/Colt/Summit, Escort/Tracer/323/Protege, Sentra, and some select others but most interested in the EF-EG Civic sedans and the NUMMI twins due to their simplicity.