IMHO,
Never go for 120gb , buy 250gb minimum. Can confirm that Samsung and adata are very good.
For hdd, you can decide based on your usage, I am using wd purple for download rig.
If you are in Chennai, ditch Amazon . I can help you get better deals.
Humble request. dont sell the older drive on Olx. Please. There is nothing bad as losing valuable data. If not you,somebody else might lose data if you resell the drive.
Do a low level format and try changing SATA cable,sata port before you lose hope on the drive