Disk Doctor & MBR Fix

I have just installed Systemworks 12 and run the tests and diagnostics.

 

Disk Doctor is telling me upon starting that it has detected a problem with my HDD1 MBR and should it fix it.

 

Now call me paranoid but the PC is booting perfectly OK and if it ain't broke.........

 

How can I find out what it thinks the problem is ?

 

Second point is that PC's quite ofter refer to the HDD's starting from number 0 so I'm thinking that if this is the case it may have detected a MBR on my second slave HDD which should not be there ?