Hi Luis,
Our moodle runs on mysql but authenticates against an mssql database used for other purposes. I've got this working now for the mean time using an older version of php that still supports those commands. We have someone else who knows far more than I do about moodle (I've just kept this installation going based on how it was previously set up by others because it's worked for out purpose) who does work for us on occasion I will need to have him look in to this further at a later date.
What were the issues with xampp? As I said earlier I've inherited this set up and just left it running as is.