Yup. D:\ (/dev/sda3) seems to me like a recovery disk.
you were not intended to use Windows much? Then you can del. that partition.
(i would first move the folders: "FactoryUpdate" and "hp" to C:\ , they probably contain windows-drivers of your motherboard.)
normally, BD-Rom Drives are Blue-ray disks., or could be a virtual drive or even build-in memory-card,
but it can't be, 'cause it's addressed to /dev/sda4
There's not much of important sitting on that drive, so you can delete /dev/sda4 as well.
Beware, I can not "really" see the contents of your folders/drives, but based on the information you posted here, i think it's safe to delete /sda3 /sda4, after moving "FactoryUpdate" and "hp" to C:\
Now, there are many things that can go wrong, during the proces, which can end up in a broken system, so please don't hold me responsible. I just gave you some sort of guide of how to pull this through, based on your information. It's up to you, if you want to do this. Good luck
oh, and sir, it's just batvink. you can leave that "sir", sir.
i'm just a normal guy, trying to help a hand where i can.
