If there are visible black veins down the back of the shrimp, make a shallow cut down their outer curves, using a sharp knife, and clean them out. Discard. If there is nothing visible, leave shrimp intact. Put shrimp in bowl with lime juice, season with salt and pepper, and let marinate for 10 minutes.
If using noodles, cook them according to package directions. Rinse under cold water until cool to the touch, drain thoroughly and put into a bowl.
Put the cucumber, bell pepper and cilantro into a large mixing bowl.
Heat butter and oil in medium saucepan and when hot add the ginger, chile and garlic. Cook for a couple of minutes or until you can smell the flavors. Add shrimp and cook until pink, about 3 to 4 minutes. Remove shrimp with slotted spoon and set aside in a warm bowl.
Now add the noodles into the pan with the buttery sauce and stir to coat them. Pour these into the bowl with the cucumber and add the shrimp. Toss salad with tongs and transfer to large warm platter. Serve immediately.