Hi Sam,
I notice the following in your screenshot:
1) C: and V: appear to be full (Size = Used).
Whether this is true or Partition Magic doesn't read them right I can't say, but it makes sense to me that Partition Magic refuses to shrink partitions it believes to be full. That would probably have undesirable results.
2) There appears to be no upartitioned space, so there is nowhere to expand the partitions to.
So, it makes good sense that the only thing you can do here is shrink D: (although it's hardly worth doing so, given it has less than 2GB free). After you shrink D:, perhaps you could expand C: into the freed space.
What did you want to do, anyway?