The most appropriate hymns to sing at a funeral would be ones that are most familiar to the audience. The words also have to be understandable and appropriate for the occasion. Hymns such as "Amazing Grace," "Rock of Ages,""Abide With Me" and "How Great Thou Art" are examples of well-known hymns suitable for funerals.
The majority of the audience at a funeral must be familiar with the hymn or hymns chosen in order to avoid awkward situations, such as the minister being the only one singing or spotty singing, where one member of the audience can be heard over all the others. Suitable hymns would include anything sung in a church service or that is available in a normal hymn book.
Some church denominations have their own songs that pertain to their personal service, so consider the denomination of the audience or the denomination of the deceased when choosing denomination based hymns.
Moreover, consider the length of the hymn and if it is time appropriate. If "Amazing Grace" is the selection, but time is an issue, consider singing only the first and last verses of the hymn. Suitable hymns would be ones that address the issue of victory over death, acceptance of death, the glory of God, the promise of life after death and general songs of comfort.