I want to ask, is my power supply (CoolerMaster extremePower 430w) are good enough for my PC spec? (check my sig + 1 DVD Writer)

And before I change to CoolerMaster PSU, my PSU was iCute 450w. Did I make a good move by changing my PSU? or it just waste my money?

And did the pc component could be damaged if I didn't turn off the main power supply when I not use the PC?

Hope the sifu can answer my curiousity~