In Ireland most people will be able to trace their families back to the first half of the 19th century. Trying to go back into the 1700s, and beyond, can be a hit-and-miss affair. It all depends on location, religion, social status and many other factors. Despite this, various surveys and listings are available from the 1700s for different counties. One example is that the oldest parish registers are from the cities of Ireland and can start as early as 1740. Records from parishes in Dublin for the mid 18th century give examples of the Buggy name. I have listed a few examples below from Roman Catholic parish registers.
A man with the rather excellent name of Dionysius Buggy lived in Dublin in the mid 1700s. He first appears in the parish of St. Andrew. In 1742 he is listed as a sponsor (godparent) at the baptism of Christina Keary. One year later, who I presume is the same person, is listing as the father of Maria Buggy as she is baptized. His wife is Winifred Buggy. Dionysius must have been a man of strong morals and fervent religious practice as he is listed as a sponsor for a further eight children between 1743-1754. Further children of Dionysius and Winifred, including Elizabeth (1745), Thomas (1749) and Anna (1753) were baptized in the parish of St. Andrew.
Denis Buggy is listed as a sponsor in 1745 at the baptism of Elisabth (sic) Moore in the parish of St. Michael and St. John.
A burial of Wineford Buggy occurred in the parish of St. Nicholas Without in 1758. Despite the difference spelling this could be the same person as mentioned above.
 irishgenealogy.ie. Parish Registers of Various Dublin parishes [database on-line]. Dublin ,Ireland: Department of Tourism, Culture and Sport, 2010. Original data: Parish Registers 1740-1950. Roman Catholic Church, Various Parishes of Dublin.