Need basic how tos before I loose computer hard drive. I have WD external HD

Hello, and thanks for stopping in.  I just found out that my computers hard drive is starting to go bad so I am looking at having to replace it.  I have done this before for a friend but it has been a while and I am not 100% confident I know what to do. 

I have the 1 TB WD external hard drive (I think it is called My Book). I have been saving photos etc to it over the years as I do a lot of photo work for my family.

I just want to be sure that I have it set up correctly to make the upcoming replacement of my computer HD easier.  I do NOT believe that I have it making a mirror image of the computer.  Instead I originally selected for it to safe certain files.  

I am hoping someone can guide me through setting up the WD HD to make a mirror image of the computer so that I can restore the NEW HD with all the programs and files I have now.  I bought this computer about 3 yrs ago from Cyberpower to do photo work.  I did NOT get a disk for any of the restore features and I do not have the programs like windows 7 64 bit , office, etc to reload.  I really do not want to loose those, I do have the sticker on the side of the computer with the Win registration info.  

Can anyone help me get saved what I need to make this easier?  Also, can you give me directions on how to start downloading the new HD with the info I save once I put the new one in?  Finally, I have a Cyberpower with Intel Core i5 CPU 650 @3020 GHz 3.19 GHz  4.0 GB RAM, 64 bit operating system - I am not sure which HD to buy - any thoughts? 

Thanks so much,

AJ

Hi, since you are trying to clone the internal computer hard drive you need a program that allows you to do that. You can try EaseUS Disk Copy Home Edition, check the link below for more info.

http://download.cnet.com/EaseUS-Disk-Copy-Home-Edition/3000-2242_4-10867157.html

Download link

http://www.easeus.com/disk-copy/home-edition/