Thanks for your interesting in our product.
In your case, if you want to keep Windows configuration and boot from the destination partition after copy, we are sorry EASEUS Disk Copy cannot help you meet the target, since all partition copy/clone features in our products can only used to transfer data (boot information is not included). Please notice that a Sector by sector copy requires the size of destination partition at least equal to original one, so in fact, you even cannot copy the C partition on 80GB hard disk to the first partition on 40GB hard disk with this product.
But our new released product EASEUS Todo Backup may help you meet the target as long as you use the 40GB hard disk in the same computer after Windows transferred, you may just try as follow.
1. Back up the C partition on your 80GB hard disk, you may put the generated image file to both D partitions if there is no other storage device.
2. Use the Recovery feature to restore the image file to the C partition on 40GB hard disk.
Here is the download link of this product and the Home edition is totally free for home user.
http://www.todo-backup.com/products/hom ... ftware.htm
More about Backup feature.
http://www.todo-backup.com/products/fea ... tition.htm
More about Recovery feature.
http://www.todo-backup.com/products/fea ... -image.htm
Please notice that the 40GB hard disk can only be used in the same computer after the process, if you connect it to another computer, it may failed to boot since the hardware configuration has changed.
EASEUS Support Team F
EASEUS Customer Support Center: