For some reason, ImgBurn doesn't seem to like burning .iso files...
I've tried different files, different disks (both CD and DVD), and tried upgrading everything I can think of. Still no dice. My log:
I 14:42:14 ImgBurn Version 2.4.4.0 started!
I 14:42:14 Microsoft Windows Vista Home Premium Edition (6.0, Build 6001 : Service Pack 1)
I 14:42:14 Total Physical Memory: 3,140,796 KB - Available: 1,778,132 KB
I 14:42:14 Initialising SPTI...
I 14:42:14 Searching for SCSI / ATAPI devices...
I 14:42:14 Found 1 DVD