Mac OS X:

Mac OS X 10.6.8
Mac OS X 10.7.5
Mac OS X 10.8.5

Mac Intel
2 GB of RAM
QuickTime
Perian QuickTime component is recommended

Windows:

Windows XP SP3 (32-bit)
Windows Vista (32-bit and 64-bit)

Windows 7 (32-bit and 64-bit)
Pentium 4 2.4 GHz or faster (or AMD equivalent)
2 GB of RAM

.NET Framework 3.5 SP1 (Note: this is already included in Windows 7)
QuickTime

AC3Filter Full is recommended

Since DualEyes is no longer updated/maintained, if it's running in an operating system outside of these specifications, the program will not be guaranteed to work as it's technically in an unsupported environment.