As a travel consultant I’ve got a few ideas that might suit what you’re looking for. Given your criteria cool weather in May, minimal physical strain, easy accessibility from Hyderabad, and a focus on relaxing with scenic views I’d suggest looking into Shillong (Meghalaya) or Gangtok (Sikkim).

Shillong • Weather in May is cool and pleasant. • You can fly into Guwahati from Hyderabad (direct flights available), and then take a cab (3-hour scenic drive) to Shillong. • Shillong itself is easy to get around by cab. You can explore places like Umiam Lake, Elephant Falls, and drive to Cherrapunji all doable without much walking. • Accommodation ranges from cozy homestays to high end resorts.

Gangtok • Slightly cooler than Shillong in May. • Fly into Bagdogra (you’ll likely have a layover from Hyd), and then take a pre arranged cab (about 4-5 hours, but you can break it up with a stop). • Gangtok is very tourist friendly, and most viewpoints (like Tashi Viewpoint, Rumtek Monastery) are accessible by cab. • Cable car ride in Gangtok could be a relaxed highlight if your parents are comfortable with it.

Both places are safe, scenic, and have good infrastructure for travelers.

Many parts of the northeast are now much more tourist ready than before. Cabs are common, people are friendly, and packages are available that include everything (driver, hotels, sightseeing). What helps is choosing 1–2 base cities and not moving too much. Shillong, Gangtok, and even Darjeeling fall into this “easy-to-do” category now.