Place red pepper, yellow pepper, celery, zucchini and eggplant on a baking sheet. Sprinkle with 2 tablespoons of the olive oil. Toss vegetables to coat, adding more oil if needed. Roast in preheated oven 15 to 20 minutes or until tender.
Meanwhile, heat vegetable broth in a medium saucepan. Cover and keep warm.
Heat remaining 2 tablespoons olive oil in a large deep skillet over medium-low heat. Add onion and sauté until translucent, about 5 minutes. Add garlic and sauté an additional minute. Add rice and mix well about 2 minutes, stirring constantly. Add wine. Cook, stirring constantly, until wine has evaporated, about 2 minutes.
Add 1 cup broth at a time, cooking and stirring rice until liquid is absorbed. Continue until rice is tender but firm to the bite, about 15 to 20 minutes. Remove from heat. Stir in the roasted vegetables and chopped parsley. Add Parmesan cheese. Season with salt and pepper.
Handy tip: Although risotto tastes best when made fresh, you can make up the Risotto with Roasted Vegetables ahead on the day. When ready to serve, reheat in the microwave.