I have Windows 7 Ultimate 64 bit and Im gonna get an extra hard disk, question is can I delete my partition on the old hard disk without reformatting so that I can make that whole drive for programs and the new hard disk for storage?
There are programs that are supposed to be able to do this like partition magic. What you want to do is format the new data drive and backup all your important files to it. Once you have your back up safe, go ahead and run your partition program. They *SHOULD* work, but in case it doesn't you have your files safe. I don't know of any free ones, try a yahoo search.
Old HDD - C = operating system and your programs. D is the partition you want to delete. First as 47454b. said Back up all your data from the old D drive. Next, play it safe do a back up image of your C drive to the new HDD, you can use windows 7 Back up to do this. Know delete D partition (from Win 7 Disk management). Then from windows 7 disk management expand your c drive partition to fill the HDD.
Get a copy of Ubuntu Linux then burn the iso to a CD then reboot from the disk next select English from the menu that appears then select try without installing after it boots live from the CD goto system administrator then select Gparted and resize your HDD from that. You may want to backup your files just in case something goes wrong.