[R] quantile type 1 perhaps?

[Francisco]

Hello,
I need to analyse some data coming from a questionnaire which have for 
each item a likert scale 1-5. I need to find the lowest scores in the 
distribution, and for this purpose I thought to use the quantile() 
function to identify the participants belonging to the 5% with lowest 
scores (who have a score < than quantile, am I right?).
The problem is: which type of quantile should I calculate? I suppose 
type 1, since it is a discontinuous distribution, but I don't understand 
very well the differences between type 2 and 3.

Thank you,
Francisco