Can I upgrade my pc with thos HDD?

Ok take note before reading this might be the stupidest question you will ever read , still I would like to get a bit of answers , becouse I'm stupid like that.
 And here goes the stupidest question. Can I upgrade my pc with this hdd , which is Seagate Barracuda 3.5'' 500GB SATA2 7200RPM 16MB to be more precise 2 of em.The motherboard that I have right now is assrock n68c-s ucc , and the power supply that I have is i-Tec PowerGamer 700w with modular cabel managment (don't know if this part is in any way necessary :D).
 Would this work or not?

 P.S. I'm sorry for my lack of knowledge in pc hardware and asking this kind of dumb question.But as it is there is nothing else that I can do.Would definetly love if anyone would help me with this stupid question.

 P.P.S In advance sorry for waisting your time and answering this question of mine.

- 4 x SATA2 3.0 Gb/s connectors, support RAID (RAID 0, RAID 1, RAID 0+1, RAID 5 and JBOD), NCQ and "Hot Plug" functions

Unless you already have 4 drives you'll be okay.

Thank you.