I'm not sure what have you tried so far, so I'll try to explain a bit.
If you just want to move the files from one home directory to another, you could run
mv /path/to/old/hdd/home/$USER/stuff ~
which will copy your files. If you prefer not doing it via the command line, you could try
nautilus (the file browser that opens when you open "Home" in Gnome).
If you don't know how to find your old partition, you should first of all mount it (which you can do easily from Nautilus), then navigate to
home/username in the old hdd, where
username is your username.
Now it might happen that when you copy the files, their ownership remains, which might bother you. Normally when you copy files to your home directory, they will change ownership and become "yours". If this is not the case, you could just create a target folder and
chmod it to force all its content to inherit ownership:
chmod 2775 target
…and then copy files to the "target" directory.
Or, you could just
chown $USER copied-files -R to gain ownership of the copied files.
UPDATE: If your home directory was encrypted, try the procedure described in this thread:
- Swapped hard disks between the two laptops
- Installed new system
- Created a user with the same username and password
- On completion I booted to recovery mode, set the old /home partition in fstab and moved the /var/lib/ecryptfs/ directory from the
old system to the new (so to have the same old keys) (backup is
advised of course)
- Booted the new system and everything worked like before
If you did not have
/home on a separate partition, you could just
- log out with your user on the new system
- move your old home directory out of the way (using root)
- copy the old home directory from the old HDD to the new one
- log in with the user that has the same username and password (
useradd it if it does not exist, or
passwd your password temporarily back to what it was on the old system)
- copy the files to some other folder that does not get encrypted (i.e. out of your home dir)
- logout again
- swap back to your new home directory (again with root)
- move the files from the temporary place to your new home directory
Hope that helps.