Can i change my 1TB HDD to a 2TB HDD? Late 2009 iMac

Question

My trusty late 2009 iMac 27 has only 55GB free. 
Can I trade/upgrade/remove and exchange the 1TB for a 2TB?

Answer 1

If you mean success at offloading, I'm afraid there is no "quick" way of deciding what to move unless you want to move everything. If you need to be more selective about what you move to the external drive, then I would suggest using Carbon Copy Cloner 3.5.4. You can dig down into each folder in your /Home/ folder and select all the files you want to transfer. This is the fast way of copying them. However, then you must come through the folders in the Finder so that you can delete the files you transferred. No matter how you do it, it can be pretty tedius.
Alternatively, you could copy your entire /Home/ folder to the external drive then erase the Home folder on the internal drive and set OS X to boot using the Home folder on the external drive. The downside of this is that the external drive must always be connected, turned on, and mounted. You do this using the Users & Groups preferences.
A third alternative is to copy only the folders from your Home folder that contain most of your files - Documents, Downloads, Movies, Music, and Pictures. Copy only these folders to the external drive. Then create aliases to the folders on the external drive. When you do this the aliases will be named as, "foldername alias." Foldername refers to the actual folder name. Copy these aliases to the Home folder on your internal drive. Now comes the slight of hand. OS X will not let you remove the original folders as long as you are booted from that drive. So, open Terminal in your Utilities folder. Use this command line to first remove the original folders then rename the alias files by removing "alias" from their filenames:
     cd ~/
     sudo rm -Rf Documents ; mv Documents\ alias Documents
Press RETURN. You will be prompted to enter your admin password. What you type will not be echoed to the Terminal window. Press RETURN again. This will only occur this one time.
     sudo rm -Rf Downloads ; mv Downloads\ alias Downloads
     sudo rm -Rf Movies ; mv Movies\ alias Movies
     sudo rm -Rf Music ; mv Music\ alias Music
     sudo rm -Rf Pictures ; mv Pictures\ alias Pictures
This will cause OS X to look automatically for these folders and their contents on your external drive. The command line will first erase the original folder then rename the alias file to remove the word, "alias."