Please make sure to look at the http://www.oilpulling.com
site, which explains oil pulling and sets forth the basic protocol for the therapy (sesame or sunflower oil, 1x/day, for 17-20 minutes). That site also has a list of illnesses and conditions it purports OP will cure.
There is not going to be a satisfactory answer for your question, as each person based on physiology and condition will have a different experience with each oil. However, some "favorite" oils around here, in addition to the traditional sesame and sunflower, include coconut (seems to be very tooth-and eye-brightening), olive (will probably discolor your teeth temporarily, though), walnut, flax...we have used a lot of oils between us on this forum. It is the consensus here that you should try to use a high-quality nut or seed oil and avoid soy, peanut, corn and canola oils (for eating as well as swishing, for that matter). It is my opinion that people brand-new to OP should try the basic protocol mentioned above for a couple of weeks and allow the body to adjust to this simple but powerful therapy, and to see if there are ` any detox symptoms or reactions that would warrant slowing down a little. I've seen several people get here, OP furiously several times a day, have terrible reactions, and then we never see them again -- better to start steadily and stick around, IMO.
Once you have acclimated, you will be on your way to figuring out what does what for you. My experience here tells me that it is not so much the type of oil as it is consistency of practice -- doing it day in, day out will produce the best and most results for anyone.
One thing you can do to look for specific conditions which OP has improved is to use the search engine. Another way to find out what commonly happens when people OP is to look at the "R" messages at the top of the forum page -- click on the "R" or "RN" or "BSA" links for particularly helpful posts. You can usually tell what a post is about from its subject line. There are a lot of "R" posts and threads where people have described the results of OP, which will be great reading for you.
Oregano is very antibiotic. I added this early on in OP and got a terrible mouth sore...ouch! But have used it since with no bad results. It's antibacterial and (I think) antiviral.
Not sure about Peppermint (other than the fact that it tastes good!)
Coconut is antiparasitic and antiviral, for starters (plus it tastes good).
I'd still do the basic OP for a couple of weeks before adding anything else. My experience with the mouth sore in retrospect might have been avoided had I not been so impatient. (Then again, maybe not!)
You can also add these to oil and apply them topically (or in the ears).
Your enthusiasm is very much appreciated. I think we all have been there. If you read some of my first posts when I started, you might get a chuckle. I was trying to put hydraulic pressure into the swishing. Couldn't figure out why I looked like a chip monk at the end of 20 minutes. Trying to figure out how to swish while driving.
After the first time I was hooked. My mouth felt so clean the next morning. Then after two weeks I started noticing some other things, particularly my skin. After a month, I was ready to go to any extreme to speed the process. That happened, but the results were a tad more than what I expected.
I don't use Wild Oil of Oregano any more. I have a very low pH that I'm having difficulty getting back up. My impression is pH levels have a significant impact upon how an oil reacts. At the same time I was trying to be Mr. Healthy. juicing raw organic veggies and fruits, taking all the good stuff. Cayenne tincture, Garlic, Cloves, Onions.... you name it, it went in the blender. I started adding Wild Oil of Oregano. I can't remember now... 10 maybe 20 drops. Holy Jesus, Mary, and Ralph, the stuff is very powerful. I now have a very deep respect for Wild Oil of Oregano, and am gradually getting back. Taking Barefoot Lower Bowl, etc.
At that time Trapper told me that yes, OOO will melt bacteria, viruses, and any parasite just about imaginable.... take enough, it will melt your organs also. So, I would have to echo Laura's advice.
On the Iodine forum they use a concept called surging. One reaches a plateau, gradually increase dosage until there is pain, and then back off for a few days. Then start again with a larger dose. So, in the world of OP, this might translate into follow the procedure. It might take a month to see the benefits, but after two weeks you might start noticing things (beyond having a clean feeling mouth). When you stop seeing improvement, then try some of those breakthrough oils. But do it gradually.
Think of it like sex. Would you prefer 4 or more hours of love making; or is the slam, bam, thank you mam approach sufficient? (I like analogies in teaching/learning a concept).
That's my opinion. No matter what you do, it will be correct.
They have some good people on this forum, and are very knowledgeable. Not only in OP, but also in some of the other areas like cleanses and alternative therapies.