It depends on your 5-day itinerary. If you visit Bwindi and Queen Elizabeth National Parks, you are almost certain to see mountain gorillas, elephants, buffalo, hippos, warthogs, and Nile crocodiles. You will also see many antelopes, especially the Uganda kob. Monkeys are common too, including colobus, baboons, and vervet monkeys.
Lions are often seen in Queen Elizabeth National Park. If you are lucky, you may also spot leopards and giant forest hogs. If you go chimp trekking, your chances are high, around 80% to 95%.
In Murchison Falls or Kidepo Valley National Parks, you are very likely to see elephants, buffalo, lions, giraffes, warthogs, patas monkeys, and many antelopes. Hippos and crocodiles are common along the Nile in Murchison Falls. Kidepo Valley is also known for zebras. Leopards live in both parks, but they are harder to see.
At Ziwa Rhino and Wildlife Ranch, white rhinos are almost guaranteed. Chimp trekking in Budongo Forest also has a very high success rate. Birdlife is everywhere in Uganda. You will see many colorful tropical bird species throughout your journey.