Zinser oil primer is wonderful primer. I have used it for years under Benjamin Moore Impervo (oil paint) and have had no problems with chipping, scratching, etc. Also the other perk is that you don't have to sand. I never sand with this priming product, even when painting over high gloss paints. But...you have to have good ventilation!! The Zinser dries in an hour so you don't have to wait long, either. I like the Satin Impervo but semi-gloss would be good too. Our house has Porter super shiny "Wet Look" enamel on it (from previous owners) now and for me it is too formal looking and I would prefer Satin or Semi-gloss.
I also use a bit of "Penetrol" paint conditioner with my Impervo. Get the best brush you can afford! I put the paint on with a brush and then go over it with those sponge things (on sticks) to smooth it out even more and to make sure there's no pooling drips, etc. The Penetrol makes it so the paint won't set up as quickly, giving you more time to work. It goes on like smooth glass with no drag at all. If you are not used to painting with oil be careful not to get too much on or it will end up sagging.
Otherwise you could go with a good latex, but I'm an oil person when it comes to trim! :) I have seen how it holds up for years and years looking brand new....

Thanks for the message...One follow up..If I decide to go with a latex, could i still use the Zinser primer?

Just finished painting wood chair rail height paneling white. Turned out great with Sherwin Wms. PrepRite latex primer and ProClassic Semi-Gloss Latex (wouldn't recommend Gloss and you might even like Satin).

Personally, I can't take the fumes from oil primer or paint any more and the latex versions are just as good any more and dry quickly. Oil will yellow over time, but latex stays white.

Use a mini-roller (the fluffy ones hold more paint than the sponge ones, so prefer the fluffy) to roll the primer and paint on, then backstroke the primer and paint with a 2.5" or 3" brush lightly to get rid of the "orange peel" left by the roller. Put on one coat of primer and two coats of paint. Sand lightly and remove dust between coats.

You will love the ProClassic. It leaves a really smooth lustrous finish.

tim022, yes you can still use Zinser oil primer if you want under latex. I have done so many times!
Don't forget the face mask (with filters) if you are going to use a lot of it.
That's the downside. Payoff is great if you can suffer through it, ...especially with NO sanding! It holds the paint on. My 7 year old kitchen cabinets look brand new. But I used oil paint, too. Maybe the new latexes are just as good,... paint has changed a lot I suppose.

Ben Moore, Fresh Start primer, Satin Impervo Waterbourne finish.

Thanks all for your information, could you also specify the actually type of primer? I checked out each and they list multiples for Zinnser, Ben Moore, and Sherwin Williams...I should also use the primer before painting the doors as well?
Thanks in advance...

Tim, the Zinsser I use is Cover Stain Interior & Exterior- Oil-Base Primer+Sealer Stain Killer Bond coat (Sticks to All Surfaces Without Sanding, Dries in 1 Hour, Use with Any Topcoat)
As I said, I have used it for many years, (under both oil and latex) inside, outside, even over tiles in a shower once, ...on floors, stairs, on floor tiles, on wood work... you name it. I have also used their latex primer and it is also a good product. It stinks too, but not as bad as the oil.
I go always for oil when I know the area may take a beating. I think both are tintable, I know the oil is. When applying, it dries pretty fast so don't over brush it/roll it. It dries hard as a rock.
Good luck! It will hold up over time, that's one thing for sure! :) The one REAL advantage of this primer verses others is that there is no sanding. That can save hours of time. The disadvantage is the smell. It will get to you big time if you are not outfitted.
(Penetrol helps keep the oil paint from cracking over time due to dryness in the house! A "pro" turned me onto it years ago, it's great stuff too!)

could you also specify the actually type of primer?

Fresh Start( little to no smell)sticks to most anything,easy clean up,do not need respirator

should also use the primer before painting the doors as well?

yes

ok - More questions...I chatted w/a paint store and he was pushing his name products (Pratt & Lambert). He offered up an oil (no smell) primer but said i'd need another primer to cover the knots in the wood (smelly) due to bleeding. Why wouldn't one primer take care of everthing?

This is a dumb question but do you prime/first coat paint then hang trim/wainscot, and final coat or put everything up then do prime/paint...
Thanks again...

If you are doing this in a bathroom, i would not only primer before the install, but prime the back of the materials as well, commonly called back priming. Then after the install, fill all fastener holes, caulk, then top coat with your two coats finish.