Kevin, the expiration date of your card is the second year of being a permanent resident. Example, if you get approved on 8/31/06 your expiration date is 8/31/08. Has nothing to do with your marriage date. The marriage date only counts to know if by the time of the approval your marriage has a lenght of 2 years or less.
The clause about the conditional residency is for people who gain their permanent residency through marriage with a US citizen and their marriage at the time of the approval is less than two years. Example, if a person got married last year on 7/31/05 and it was grant permanent residency on 4/25/06 that person receives a conditional card. Because the lenght of their marriage is less than 2 years by the time of received the residency.
The second part refers that if you were admitted in the US with an immigrant visa (if the spouse goes through Consular Processing/means you apply for your spouse outside the US) or Adjustment of Status (within the US). Does not matter where the marriage took places is the lenght of the marriage.
If you were married 24 months at the date of received your approval you should received a non conditional card but if you were married e.g. 18 months you should received a conditional card.