As far as I know all certificates ordered from GRO or the district offices are the same - they are a photocopy of all the details entered in the Register on the day the birth was registered.
The certificate I have (birth 1885) has DOB, address where born, child's full name, sex, fathers name, mothers name and maiden name, fathers occupation, informants name and address, the date of registration and the registrars signature.
Perhaps the person who told you about the standard/small certificate is getting confused with when you register a baby you are issued with a short certificate - which just shows the date, baby's name and where born but you can also pay for a full certificate which shows the parents details etc.
I am sure other members on here have more experience of ordering certificates than me though, so they may know more.