Install in Second Partition

Hi, I would like to install Linux, via FTP, on my machine; in a second partition, first partition is Windows. I did a defrag. But am not sure if all sectors have been moved to beginning of disk. If the Linux part overwrites some of these unmoved sectors, then Windows will not work right (what else is new?). Am I ok, as it is now? How can I tell if there are sectors that must be moved? What can I do to move sectors if need be? Thanks, Roger