Yes, VoiceOver can read PDFs, as long as they are indeed text PDFs and not just pictures of text.
Open the PDF in Preview. Set the options using the View—>PDF Display menu command. You can choose between Single Page and Single Page Continuous, depending on how you want to read.
Then navigate to the "scroll area" (VO-right arrow repeatedly), then type VO-A. If you're in Single Page mode, VoiceOver will read an entire page, then stop. To move to the next page, press Page Down (or fn-Down Arrow on a laptop), then repeat VO-A.
In Single Page Continuous mode, VO-A will read the entire document. To pause in either mode, press Ctrl on its own. To restart, press Ctrl once more.
Should your PDF turn out to be a picture of text, you can convert it by running it through an OCR program such as Abbyy FineReader Express or ReadIRIS.
HTH
Archie
(Note: VO is shorthand for Ctrl-Option)
PS: You might find it helpful to join the
Mac-Access mailing list.