IIRC, the direct Burn to DVD was removed in CS3 (was there in CS2). However, you have one of the best non-mega-buck authoring programs, Encore, bundled with PrPro. I'd use it. This side of about US$50K, you can't do much better.
Now, I'm on the PC side of the street, so some of what I do might not translate to the Mac-world. Still, here goes. I always Export from PrPro as a DV-AVI Type II elemental stream (no Audio) and an AC3 DD 5.1 SS elemental stream (Audio only - and I use the SurCode DD 5.1 plug-in). I Import the AVI as a Timeline into Encore, and the AC3 as an Asset. I drag the Audio to the Timeline and it's good to go. In nearly every Project I let Encore do the Transcoding with its "automatic" setting. I've only had to do bit-budgeting and Transcoding in PrPro about 3x, out of several hundered Projects.
Now, the AVI is a problem with the Mac, so you'll probably be working in .MOV, or Transcoding to MPEG-2 in PrPro. Do not know about your Audio, as I do not think that WAV is common on the Mac. AC3 (stereo, unless you have the SurCode plug-in and need the 5.1 Audio) is a possibility, but do not know if Mac's handle these. I'd still look to Exporting (Mac friendly formats and CODEC's) as elemental streams, not muxed files. Do the Import, as per above.
If you did not install Encore, you will want to do that. Also, in CS3 there are some early attempts at full Dynamic Linking between PrPro and Encore. Do not know how well they work. Still, the Mac adaptation of my workflow above, should get you there.
Should you have any questions on Encore, Adobe has a FORUM for that program. It's broken down into several sub-fora, but there is a general Encore area if you cannot decide in which sub-forum your question should go. Most users there are on PC, but several have Mac's in their studios. As of CS3, a lot more pure Mac users have been showing up.
BTW your file will end up going to MPEG-2 (the format of DVD-videos) at some point in the process.
Wish I could be a bit more specific, regarding things Mac, but I am just an old PC-guy. I'll look for any questions you might have on Encore in that forum, in case they are not platform-specific.
I'm addressing the last part of your question separately, as it's pretty much a separte issue. After my comments above, these are my steps to insuring the most reliable DVD discs, out of Encore:
1.) start with elemental streams for Import into Encore (see previous post)
2.) let Encore choose the Transcoding bit-rate automatically
3.) use top quality media - Verbatim and Taiyo Yuden have been proven to be about as good as it gets
4.) use the slowest burn speed that you can. This is based on both your media, and your burner. Encore lets you set this. Choose the slowest!
Test in as many computers (software DVD players) and as many set-top players, as you can. I have 5 different players of all levels from true esoterics down to US$99 players. I test in each. If the disc will play in all of those (and 99.9% of my burns do), chances are pretty good that it'll play almost anywhere. Remember, no DVD player is *required* to play ANY burned DVD - only replicated, pressed commercial DVD's. Most do, without a problem (see above to help eliminate most problems), but some just flat will not. That is a minor number of players, but your client could be the 1 in 10,000 and other than buy him/her a better player, you'll have to think about replication, and not burning. Actually, buying them a top-of-the-line player would cost less.
Good luck and you'll find more details on the Encore forum.