Can Older Dvdrom's Read Dvdrw's?


I need to archive a lot of files and DVDRW's are the cheapest per gb, changeable, portable storage available I've found at about $.15/gb.

My query is I'm wondering how far back in the G4 lineup can DVDRW's be read? Can any DVD-ram read them? Can any combo CD-rw/DVD-rom read them?

Can any Mac read any external drive or do I need software drivers for each? Maximum compatibility with the rest of the Mac world is crucial. Speed is not.
Any written DVD-/+RW (even dual-layer) should be readable in any DVD-compatible drive. But I didn't test this in practice. However, considering the speed for burning DVDRWs to DVDRs and also their prices, DVDRs should be the better choice. In CD-times it was said that CDRs are much more compatible and more robust than CDRWs. Not sure if this also applies to DVDs..