Hi Jeanette!
Congratulations on planning a trip to Walt Disney World in May. Your two boys are going to have the best fun, and you will all enjoy making so many magical memories together.
While your two-year-old will not be permitted to ride the really big attractions, there are many more opportunities for you all to ride together.
Take a look at the attractions for each park, you will see there will be height restrictions listed for each one, and if it reads 'any', you will be able to ride together.
Magic Kingdom Epcot Hollywood Studios Animal Kingdom
It may be worth remembering that it might be possible for a Cast Member to look after your two-year-old whilst you ride with your older son. I have heard that this happened at The Twilight Zone Tower of Terror at Disney's Hollywood Studios. Nothing is guaranteed regarding this, but it is always worth asking at the attraction entrance.
If I can help you with other planning questions for your trip, please come back, especially regarding details of specific attractions, or other shows and entertainment at the parks that your family would enjoy. I would be happy to help you plan your vacation.
Have a magical trip!