In the interview always be honest, otherwise it will take a long time to convince other side of the table.
Now coming to the weakness part -
No one is perfect and its best approach would be to show awareness of a weakness and then explain strategies that you have taken or that you use to overcome that weakness. In short try to turn the negative into a positive.
No one is perfect and interviewers will appreciate your honesty, maturity and self-awareness and most important that you are able to learn from weakness to improve yourself.