How should a Muslim react (within himself) when he sees a disabled person? Should be recite adkar of gratitude, adkar of zikr, pray for easiness for the disabled person, etc.

The Prophet salla Allahu alaih wa sallam said: Whoever sees a person who is afflicted with some trial and says, ‘_Al-hamdu Lillaah alladhi ‘aafani mimma abtalaaka bihi wa faddalani ‘ala katheer mimman khalaqa tafdeelan_ (Praise be to Allaah who has spared me that with
which He has tested you and has favoured me over many of those whom He has created),’ that trial will not befall him.

Please visit here for detailed fatwa information directly from highly respected scholar