For pest control in the garden, garlic, oregano, tons of basil, sage and rosemary! OH and borage of course..
for medicinal many have to be started from cuttings..they just are hardier..but if you greenhouse you can do them from seed!
I grow borage, chicory, chives, wormwood, bergamot, bay leaf, echinacea, fever few, rue, lavender, lemon balm, marjoram, mullein, parsley, patchouli, sage, stevia, all mints, yarrow, poppies, goodness..there are so many...
some are used in foods as well as for medicines..I make teas/tisanes mostly and some bath and skin care products as well.
I love herbs...and believe that they make the very best landscaping material!
here is a great chart on what they can be used for..I have tons of books I use!
http://www.herbsguide.net/