We used to read Qur'an in Arabic but I don't understand Arabic so if we read it in our language. Is it good?

Praise be to Allah, the Lord of the World; and may His blessings and peace be upon our Prophet Muhammad and upon all his Family and Companions.

It is not permitted to recite the Qur'an in any other language except Arabic, whether one is in prayer or not, or knows Arabic or not. This is the opinion of al-Malikiyah, al-Shafi'eyah and al-Hanabilah. Only Abu Hanifa legalizes reciting the Qur'an in a non-Arabic language in prayer for the one who cannot recite in Arabic. But, we think that the first opinion is the dominant sound opinion.
Allah Says (interpretation of meaning): {In the plain Arabic language.} [26: 195]. He also Says: {Verily, We have sent it down as an Arabic Qur'ân in order that you may understand.} [12: 2].
Thus, it is not permissible to recite the Qur'an in a non-Arabic language on the plea of being incapable to understands its meaning. But, there is no harm to explain and expound its meaning and rulings in any language.
We ask Allah, The Exalted, to help you understand the Qur'an and to put its orders into practice.
Allah knows best.