The best way is to use compression to get it under 700 MB or use multiple CD-Rs.
Any kind of overburning is uncertain because you don't know if it will burn for sure, and you don't know if all drives will be able to read the result.
Another option is the high density burning available on some plextor drives. Of course, you can never be sure if a non-plextor will be able to read it back...
Just find a natural way to get your data down to under 700 MB. That is the safest and most effective way to do it.