Okay, you`ve got 4 partitions. Win7 should be installed, and partitions 3 &4 should be untouched. What about the 2 "untouched" partitions (former 3 & 4) - just data, or is there an OS installed? If just data, you should install like that: Partition 1 & 2 can be deleted at Win7-Setup. There`s an option "Extended" (or like this) when you boot from DVD, you`ll see the Partitionmanager. If you first delete 1 & 2 and leave the others untouched, you have left 172,1 GB free space and the former 3 &4 - now as 2 & 3. Now you install Win7 in the free space, and everything should be fine.