Read the OneWorld Minimum Technical Requirements page.
I would go to the most recent Service Pack available. JDE puts so many of them out. However, do not order any service pack with a .0 suffix, for instance, 16.0, 17.0, 18.0. You may need to choose a level based on your operating system version or which Update you choose. Also, they put 3 Update's out a year. Since they are cumulative in nature, I would also go with Update 4 vs. 3, but again you need to look at which Service Pack you will load. JDE likes you to stay current on Updates and for us, moving to a new update requires a whole new set of integration testing, so we pick the newest so we can stay on one Update per year. We're loading Service Pack 17.1_E2 this weekend. We've been testing a month and already there is a Service Pack 18.1 out. Next week we're loading Update 4 into DEV/CRP and will go live with it in April. An Update level is like going to a whole new version of World. A Service Pack upgrade is more like just the System, Foundation and Programmer systems in World.
Jean Driscoll
AS/400 Co-existent Xe SP15+17.1, Update 1/A73Cum12