In a medium bowl, mix the pepperoncini, sliced olives and 1/4 cup of the oil. Add the bocconcini and toss.
In a small bowl, whisk the lemon juice with the vinegar, garlic and oregano. Whisk in the remaining 1/4 cup of olive oil and season the dressing with salt and pepper.
In a bowl, combine the shredded lettuce and salami. Add the marinated bocconcini and half of the dressing and toss well. Transfer the antipasto salad to a large platter.
Top with the basil and capers. Drizzle the remaining dressing around the salad and serve.