In this paper we study the existence of a unique solution to a general class of Young delay differential equations driven by a Holder continuous function with parameter greater that 1/2 via the Young integration setting. Then some estimates of the solution are obtained, which allow to show that the solution of a delay differential equation driven by a fractional Brownian motion (fBm) with Hurst parameter H > 1/2 has a C (a)-density. To this purpose, we use Malliavin calculus based on the Fr,chet differentiability in the directions of the reproducing kernel Hilbert space associated with fBm.