Mujawwad is an adjective that comes from the noun tajweed which means pronouncing the words and letters of the Quran correctly and according to the classic Arabic.
As opposed to Murattal, multiple types of sectioning are used in regard to its phrase lengths.
The vocal quality of Mujawwad can be relaxed, tense, or alternate between the two, to create a dramatic effect.
The Melismatic properties of Mujawwad can be quite extensive as compared to the mostly syllabic content of Murattal; Quran recitation.
Murattal is the adjective of the noun tarteel, which is reciting the Quran in a slow mannered pace.