It's an IDE burner that's a holdover from another computer. I have it connected through a VIA VT6421 card. I actually found an updated controller for the VIA card which is Windows 7 64 bit compatible, but it didn't help at all.
It's still acting like it's media related. IMGBURN finds the drive immediately when it's empty but sometimes has trouble finding it when there's a blank disk in it. If I put a disk in it after I open IMGBURN, it takes forever to pull up information about the disk.
However, the issue didn't start until I upgraded to Windows 7 64 bit from Windows 7 32 bit (the 64 bit OS allows me to use more RAM on my computer). Also, it happens with my DL media and my plain old DVD-R's as well. Oh, and it's the same disks I was using before the upgrade.
I'm starting to give up. I ordered a new Samsung burner that I'll try when it arrives.