If you know the recipient likes scotch, then you should get him his preferred brand. If you're not sure whether the person likes scotch but want to give scotch, a blend is appropriate because they tend to have more mass appeal.

Before you give a single malt, be sure that the person likes its flavor profile! I hate Laphroaig, for example - it tastes like you retrieved the bottle from the burned out wreckage of your house.