Having have played both piano and organ for civil and church weddings for some years, I am always surprised at how cautious brides and grooms are in their choices of ceremony music. There are so many suitable pieces out there - classical, popular, and in-between. Perhaps we wedding musicians are to blame. After all, when you ask us for ideas, we are very likely to suggest the pieces we played at the last wedding, so we can get away with as little practising as possible!. The proliferation of wedding music CDs with similar playlists also perpetuates the myth that only certain pieces are allowed.
The first rule for a successful choice must be: choose music that fits in with the atmosphere you want for the ceremony, but only have music that you would enjoy listening to in your own home. So, if you only ever listen to popular music, don't feel that you must have classical music on your big day just because you think it is the 'done thing'. If you are getting married in a church, bear in mind that most churches use hymns written in popular styles, so ministers are unlikely to refuse anything as long as the words are suitable. Musicians enjoy being challenged to play unfamiliar items, and given the huge repertoire of songs to be found on the Internet as MIDI files, they should be able to find the items you want and even create their own scores to play from. Whatever pieces you choose, unless you already know them well, try to listen to them a few times before the wedding so that when the day comes they really mean something to you.
The second rule is: take your time and do your homework. If you go to your musician expecting to make a choice within a single session, the chances are you will go for the first items played to you that you happen to like. If you hear several pieces you like, you will find it hard to choose between them 'on the spot'. Of course, you can never make the perfect choice. There are thousands of pieces you might like if you had the chance to hear them, but that you have not yet heard because you don't have the CD, or your musician either does not know them or has not had time to play them. That is why when brides and grooms come to see me for ideas, I play a few pieces through to them, see what they like, and make a written note of 'possibles' for each part of the ceremony. I then invite them to take the note away with them and mull over their choice.
The first music you are likely to need is for when the guests assemble, in church or other ceremony location. For this it is best to let the musician(s) choose something to suit the atmosphere. For a civil ceremony, discreet improvised `hotel foyer'-type music works well, as it can be played for as long as needed, and adapted to the background noise level from the number of people present at any time. However, set pieces may be included if desired, perhaps just before the bride is scheduled to enter - but remember that if the bride arrives late the musicians will have a gap to fill and the continuity may be spoilt.
Music for the bride's entrance should always put over its message in a short time - unless you are getting married in a cathedral, it will not take long for the bride to get from the door to the altar, or to the registrar's table. Baroque music with short repeated phrases fits the bill very well (this is perhaps why Pachelbel's Canon is so popular for brides to come in to), but though the music chosen may be bright and cheerful, it should not be frivolous.
When choosing hymns for a church wedding, try to find ones that really mean something to you. Unless the congregation is made up of regular churchgoers, or you have a strong choir, use well-known hymns, and check that the organist will play them in keys that are comfortable for people who do not sing regularly. There are few things less enjoyable than having to sing hymns you do not know that have notes in them that you cannot reach. Read through the words and make sure you like and understand them, and that you want to hear your guests sing them. Leave out any verses with high-flown Victorian language or obscure meanings. Don't be afraid of using hymns intended for children that convey a simple message.
The signing of the register and photographs usually takes around five minutes, and may take longer at civil weddings, where guests are often invited to come up and take photos after the official photographer has finished. The music chosen should therefore collectively be capable of covering this period. If in doubt, choose music that might be too long, and ask the musicians to cut it short if needed. If you are having solo singers, make sure that they stand at the front and are not used for background music - singers find it very hard to perform when people are talking, but other instrumentalists can usually cope. There is a huge potential choice of music. I recommend something with a good tune and a flowing accompaniment that can be both enjoyed by guests wishing to sit silently and listen to it, and used as background music by guests wishing to talk amongst themselves. If the bride and groom remain within sight of the guests, the pieces should not contain dramatic outbursts, that divert the guests' attention from them. Many popular ballads and classical pieces with titles such as `nocturne', `barcarolle' or `song without words' and slow movements will do very well, but be wary about inadvertently creating a 'sad' atmosphere by using pieces written predominantly in a minor key (eg, most of Chopin's nocturnes, or the first movement of Beethoven's 'Moonlight Sonata' - which I actually was asked to play for a wedding on the day of Princess Diana's funeral).
Music for the exit of bride and groom should be long enough to also cover the exit of most of the guests. Tastes vary greatly on this - some couples may like something `light and bright', similar to the music the bride might enter to, others may like something grand and stirring, and yet others might like something romantic. This is usually the hardest music to choose, and where the church organ comes into its own. If you are having other instruments playing, avoid anything that forces them to play at maximum volume to create enough noise. Otherwise, if you are just having piano, you might end up with something that sounds like the accompaniment to a silent film!
Finally, whatever you choose, make sure your musicians are happy about playing it. For example, if you are getting married in church, there is no point in going for Widor's Toccata, unless your church has an organ with at least two manuals (ie, two keyboards) and pedals, and an experienced organist. Otherwise your wedding video might just end up on 'You've Been Framed!'.