This is going to depend on the model DVD burner and which blanks you use. Some of them can burn DVDs with fairly good compatibility, and others are poor. Do you know what the model is?
The only 8x DVD burner Dell shows is the Plextor® PX-708A. This is a well regarded drive.
When you shop for a DVD player, bring a burned DVD with you and try it out. You could even bring DVDs in a couple formats. You may not be able to get away with any old $39.99 DVD.