So I bought a new hardrive. Before putting it in I backed up most of my data. I unplugged my old hdd(which has win xp 32 on it), and installed my new hdd. I booted up and installed a new copy of windows7 x64 on the new hdd.
Now I realize there is still some data I need on the old hdd. Is there anyway I can get that data off of my old hdd?
If I just plug it back into my system, will the data be corrupted due to the fact that there is a OS on the old drive??
Nope, your data won't be corrupted due to an older OS. The only thing is before you start Windows, make sure the hard drive with Windows 7 is the boot drive. I've done with an old Windows 95 hard drive and Windows 98 hard drive on a XP system. Windows 7 will just see it as another hard drive.
If it's a sata just plug it in and make sure that you select your new drive as the first boot device in you bios. (You can boot to either drive, by selecting which one to boot first)
If it's an IDE, just make it a slave drive and boot as usual.