I have used OpenOffice (or StarOffice) on Macs for many, many years and you do not have to figure out which version of Java to use. Just load the latest version of Java and OpenOffice will run fine.
OpenOffice's finickiness with Java might have been an issue on Linux boxes circa 2002, but those days are long gone, particularly concerning Macs.
Dicking around with Java versions is a Linux thing, not a Mac thing. It's one of the reasons why the system administration load on a Linux boxes is much higher than the sysadmin load on Macs.
Lots of people have been using OpenOffice and vlc on Macs for years, so I don't know what else to say.