This won't help you, but it was one of the features of the early versions of ghosts that bothered me (the last version I used was Ghost 2001). It would only restore to a partition of the same size.
Scenario 1: (the "right" way to do it) - restore to partition of the exact same size as the original partition you ghosted
Scenario 2: restore partition to a bigger partition. When it's done and you boot into the OS, it detects it as the smaller partition's size. I haven't figured out whether the rest of the drive's space is visible to Windows. You probably should check in disk management to see what it sees.
Scenario 3: restore partition into an unpartitioned space. this is the one that irked me the most. it would use ALL the unpartitioned space, no matter how big, and when you reboot, the OS would think it was the old partition's size (not matter how small it was).
I've never really figured out how to remedy this (I just ghosted to similar-sized partitions thereafter). It could be the partition table has the wrong data and thinks the maximum size of the drive is the old drive's maximum size. Or maybe it's only using the 160GB of the 1TB (as I said, Disk Management would tell you this). If disk management only sees a 160GB drive, then my 1st hypothesis is right. If it's the second scenario holds, then just use a utility to resize your 160 partition to fill up the 1TB.
The rest of this is to try if you still have your data on your 160GB drive.
In the future, try XXClone. It clones the drive, regardless of file system and partition size (it does a file-by-file copy, so the drive has to be partitioned and formatted beforehand - it won't do it for you like ghost (sometimes wrongly) does).
Another safe way to do this is to create a 160GB partition on your 1TB drive (it has to be exactly the same size as the original partition - down to the megabyte), do your clone, then partition the remaining space as your D: drive, or use a partition resizing utility to stretch the 160 to use up all the 1 TB (BTW Windows Vista has a built-in partition resizing utility - XP doesn't).
I'm surprised Norton doesn't have documentation to address this. Look in the manual. Maybe there's instructions on how to clone your old drive to a new, bigger drive.
In the Ghost 14 manual (1st hit on google is a pdf, in chapter 15) it specifically says to use the "copy drive" option in the main menu, and there's an option that says "resize drive to fill unallocated space". I don't know if version 12 has that option.