Not exactly the same. They are members of the same genus, Pelargonium, but have been hybridized from a few species specifically for scented foliage. Flowers are not nearly as showy as zonal geraniums and the plants are often large and rather rangy looking in appearance. And not frost hardy. A few may have some insect repellent properties, but the same can be said of a lot of plants with pungent foliage and I doubt any will provide a sure control. Select those that have a citrusy scent.

I've heard that white geraniums (zonals) are good bug repellants in the garden. The scented geraniums (pelargoniums) are grown not so much for their flowers but for their scented leaves. Both types will not take freezing temps and must be brought in or die in all but z8 and warmer. Scented geraniums come in wonderful fragrances like lemon, rose, chocolate mint, orange, pineapple, lime, nutmeg, cinnamon etc... are easy to propagate and release fragrance when you brush up against them or touch them.