How many partitions do you have on the 80 GB disk? And have you connected the 1 TB disk to the computer?
I have XP installed in C Drive. I boot into XP itself, run DriveImageXML, and make a ghost image of C Drive. When I want to restore the image to C Drive, I boot into Win 7 (installed in another partition) and restore the C Drive image.
What you can do is this: Boot into your Win 7. Open DriveImageXML, and click backup. I'd add pics but the Printscreen button on my laptop doesn't take snapshots of the screen. I think you'll have to run DriveImageXML as Administrator to continue. Run it as Admin, click backup, select the partition you want to backup. Click next; it will ask you where you want to save the partition image.
If your entire 80 GB disk is one partition, you'll have to save it in the new 1 TB disk. I don't think it'll allow you to save an image of the 80 GB disk onto itself, because it locks the disk when it is making a ghost image. So first make an 80 GB partition on the 1 TB disk, the first partition. Lets say you have made two partitions on the 1 TB disk, one is an 80 GB partition for Win7, and the other is D drive, for data. In DriveImageXML, save the ghost copy to the D drive of the 1 TB disk. After it has finished, click Restore, select the 80 GB partition on the 1 TB disk, and select the image file from the D Drive of the 1 TB disk. Wait for the process to complete. Now you have two Win7s, one on the 80 GB disk, and another on the 1 TB disk!
So: connect both hard disks; make a copy of the 80 GB disk to a partition of the 1 TB disk. Then restore the image to the first partition (C drive) of the 1 TB disk.
When you are saving the ghost image, it'll give you a couple of options: one is Raw mode - it means DriveImageXML will make a sector to sector backup, including the free space, and make an exact copy of the partition selected. You don't need that, you just need the data of Win7, so don't select Raw mode. You can choose whether to split large files, it is selected by default and is better kept that way. Choose the kind of compression you want, I keep "Good", it is slow but it saves disk space. No need to do anything with the "Hot Imaging Strategy" section. And yes, if you have a lot of personal data on the partition you want to backup, like images and stuff, it is better to shift that to the 1 TB one first, to the second partition. This will speed up the backup process as there will be less data to backup, and the image file will also be smaller.
In the end, you can use EasyBCD to edit the boot entries, and add an entry for the Win7 of the 1 TB disk.