If you plan to keep the oil and vinegar separate until putting it on your salad I would put the herbs in the oil, not the vinegar. People pack peppers in oil for storage (not sure how long it lasts, wouldn't store it for years that way but a few weeks in the fridge is likely fine).
As far as what type of herbs, if you like Italian dressing then use an Italian herb blend (they
sell it already mixed -- McCormicks herb blend contains marjoram, thyme, rosemary, savory, sage, oregano, and basil.). Or if you have a favorite store bought oil and vinegar dressing then look up the list of ingredients and see what spices they put in it. I also wouldn't strain the herbs out just make sure they are in small little pieces like store bought Italian dressing.