Are you sure you are using Microsoft Money 5.0 and not 2005?
If you are wanting to delete the oldest year, Archive will delete non-investment transactions before a specified date. People often warn against using Archive, because what it does is not most people had in mind. They had the idea that Archive would make
their file significantly smaller or faster.
Also, Advanced Find and Replace could help, but that would still be tedious if there are many entries for the year you had in mind. That probably worked differently in Money 5.0