DVD/CD for an Acer Aspire Z5600

[ninig]

My dvd rom is not working wont take cd and makes a noise, will it be worth replacing it or should I just get an external dvd/ cd

 

[ninig]

I also have a Dell Inspiration 4700 that the on and off switch went bad. It has power therefore I dont think has to do with the power supply. I need some answers please on this two postings. Thank you