Currently a bind-over is used when no conviction is recorded. It is up to the prosecutor to suggest that the bench impose a bind-over, and if they do, the defendant has the right to refuse. (If he does, the prosecution then have the option to begin a normal prosecution.). I’m not sure, but I believe this was the case twenty years ago when your incident occurred.
If so, the answer is that you do not have a conviction, and you did not receive a warning, so you can answer “No” to those two questions.
However, the bind-over must have been recorded against your name (if for no other reason to have a record of it should it have been broken). How long that record would have been kept, and whether it would show on an enhanced CRB I could not say.
If you are asked whether you have ever been arrested then you should say yes.
On a wider note, your quandary is typical of the situation many people now find themselves in when asked to prove their “innocence” when they may not have been convicted or even charged with any offence. Many employers now ask a question along the lines of “Have you ever had your fingerprints and DNA taken and retained by the police?” Increasingly large numbers of people, unconvicted or even not charged, must now answer that they have. It has created a third class of citizen: those who are innocent; those who are guilty; and those who have been involved in an incident of some kind but not charged or convicted of an offence. Those, in fact, whose details the police like to hold on to, “just in case” - not quite innocent enough for their liking.