In Acrobat 6 - and I'm sure 7 - you go to Print and select the right PPD. Then you click on Advanced and teh whole print thing is there. Output to separations (or other), screening, rasterization, etc.
On the Advanced menu there is also separation preview.
Basically, you've got a printer who is having you do his work and taks any blame. So if a Pantone solid blue comes out purple he can blame you. Also, what version of Acrobat does the pronter have? He might be too scheap to upgrade.
It would probably be easier to upgrade to 7 so that you're not messing witht he OSX/Classic thing, but 7 is not going to give you any better better result than printing psotscript separations and distilling.
Using OSX 10.3.9 on a G4