The best advice is to watch the domain sales at a place like DNJournal (
http://www.dnjournal.com/domainsales.htm) and see what's selling and for how much.
If you're looking to park or for resale, the closer you get to single meaningful words and short phrases the better you'll be. At DDC, we look for quality type-in traffic - domains such as CheapCars.com, ForSale.com, Divorce.com.
Look at your budget and decide. Do you want to invest in a couple of very good names or lots of not marginal names? Quality should win over quantity every time.