You have your data backed up, there's no reason not to start afresh. Unless you're not sure you copied everything over properly
So, that should be option D
Rsync your /home partition to the NAS (assuming it runs Linux and
has rsync installed
), double check everything is there. Insert install CD (DVD) and install properly: create partitions for /boot, /, /home, swap and if possible /var, /usr and /tmp too. Don't make these too small, especially /var could need some extra space as this is where variable settings are stored. In general, none of my partitions (except for /boot) are smaller then 7 GB (/boot is usually 1 GB). Make /tmp large enough to hold at least a DVD's worth of data. Note that the rule about swap being twice the size of the installed RAM still goes, but if you'd install more then about 4 GB of RAM, it really takes up just space you'd be better off using for /home.
There is, however, another alternative: option E
Rsync as above, but install to a new drive. Install a small SSD (about 30-40GB, these are relatively cheap) and use that to install your new system. Then mount the old disk as data disk for /home, clearing the old partition of unwanted stuff. Not only have you now physically separated the system and your data, with an SSD you'll now notice a considerable increase in speed, mainly cutting down boot times