There may be a matter of correct and current drivers in the OS X for the late model
external Samsung USB optical drive, for compatibility. Does the product nomenclature
suggest which Mac OS X versions it may be used with? If Leopard 10.5.8 is not stated
and if there is mention of Intel-based processors, then your old PPC G4 can't use it.
Usually the peripheral vendor or manufacturer may state on the package, its limits.
The change from PowerPC to Intel-based Macs left two groups of almost parallel
development at a time, so most newer items for Mac, especially USB support for
old computers, is not so likely. A newer model Samsung optical USB external drive
would be fairly matched with a newer Intel-based Mac, but not PowerPC G3/G4/ etc.
http://burn-osx.sourceforge.net/Pages/English/home.html
There may be a useful older software in a free version of Burn. This item may not work
with the newer Samsung, but usually works (if you get correct version for Mac + OS X)
and can be helpful with other localized burn software won't work... No guaranties.
If Samsung states on their product package, their product may be compatible with older
Mac OS X versions, and in with the PowerPC computer hardware build series, then it
may be able to work under certain (undisclosed?) circumstances. But it probably won't.
Sorry to not be able to offer a support reply of definite yes or not, for a non-Apple product
and for an obsolete hardware/system question. FireWire400 would be the best bet.
Good luck & happy computing! 🙂