Pleasure is everything we enjoy in this life; such as health, free time, food, drink and others.
On that Day, Allah (swt) will ask the man about the blessings that he enjoined in this life, the right of the blessing over you is to praise the giver and thank Him, only then, you will not be asked about on the Day of Judgement. For Allah (swt) will is going to ask each person about the blessing he has favoured him. Abdullah Ibn Az-Zubayer (may Allah be pleased with him) narrated that his father said:
When the verse (Then you will surely be asked that Day about pleasure) was revealed, Az-Zubayer asked: O’ Messenger of Allah, what pleasure we will be asked about, we only have the two blacks; dates and water? He (saws) said: (Indeed, that will be)
Thus, the pleasure is the healthy bodies and healthy vision and healthy hearing, that, on the Day of Judgement, Allah (swt) will ask His salves about what they have used them for, although He (swt) knows. Mujahed said: All the pleasures of this life are blessings, so the first thing to be asked about on the Day of Judgement is: have we not given you a healthy body? Have we not given you cold water to drink?
 Sunan At-Tirmidhi, Book of Tafsir, hadith No. 3356.