I get something a little different here....at least two DK albums means we want to choose either 2, 3 or 4 of Diana Kroll's albums.
Choosing 2 we have C(5,2)*C(11,2) = 550 ways
Choosing 3 we have C(5,3)*C(11,1) = 110 ways
Choosing 4 we have C(5,4)*C(11,0) = 5 ways
So 550 + 110 + 5 = 665 ways
And that's the direct method
For the indirect method, we want to take all the possible ways of choosing 4 albums and subtract the ways that don't include choosing just one or none of the DK albums...so we have....
C(16,4) - C(5,1)*C(11,3) - C(5,0)*C(11,4) = 665 ways