Do not know quite how to transfer data and OS (Win 7 64 bit), etc., from current, damaged hard drive to a new one (both SATA). Have connected the second HD, in an external HD enclosure, to the computer by the connecting cable but what to do next is not clear.
Is software needed to transfer files, etc.?
Have discs for installation of OS and other original drives, software, and so on.
An easy way to do that is by using cloning software, which clones the contents of the source drive over to the destination drive. I am unsure of any good free disk cloning software, and i only have experiance using Symantec Ghost in a corprate environment (and Ghost costs money).
Never a better occasion for getting Windows installation experience!
It's advisable to disconnect your old drive before the installation. This way you won't have to choose between devices during the installation, so less chance for a mistake. And it won't make a mess with bootloading (if you have two drives, sometimes the bootloader gets installed on one drive and the system on another, and when the one with the bootloader gets removed, the other won't start).
Then onnect the new one directly,and go forward with the installation. What's the worse that can happen? You can start all over again.
A clean install is especially recommended if the "damage" in the old drive (bad sectors??) affected the system files.
After the successful installation, you can install the necessary drivers and software you use, and then you can reconnect the old drive, and copy over your own files with the standard file copy mechanism of the operating system.
For your own files (e.g. files that you created like MS Word files, or music files/movies etc.) it's quite simple.
If you have saved games, or browser bookmarks, you'll have to check the actual software's recommended method for bringing those over. For example browsers can export and import their bookmarks. So you are supposed to export them now, on the working system, so that you'll be able to import them to the newly installed one.
Transition between systems can be a little painful sometimes, especially if you are using the old one for some times, and you have everything in its used space. But in this case, you can go back (boot into) the old system later, in case you had forgotten something.
Err.. damaged HDD is the data (file integrity) still safe?
cloning The drive will give u the best result u can get but it will stress your HDD (reading data).
there are many cloning software there free and good one (I used acronis true image WD free edition), or for better support the company by buying them
edit: if the data integrity is bad than as the poster above says disconnect the bad HDD, connect the new one and reinstall all. After done reconnect the bad one and salvage any data that can be rescued