Hi
We live in Glasgow and have 2 villas in Florida. We therefore travel back and forwards 2,3 or 4 times each year from Glasgow to Orlando for the past 13 years.
We must have used every airline - direct and indirect.
My advice is - direct if possible. This is now very limited - Virgin are my number one choice but they only fly from Glasgow around 12 times per year at school hols - so April, late June, July and October.You can check the exact dates on their website.
They also fly direct from Manchester twice a day to Orlando International and it is much cheaper but you have the drive from Glasgow - OK on the way down, not so great on the way back.
Indirect - either via Gatwick (BA or Virgin) but connections not great on the way back or Amsterdam or other European hub.
I would however recommend if you are going Indirect using one of the American airlines - the options from Glasgow are now limited to Continental via Newark (good times and connections, service not great, usually cheap) or US Airways via Philadelphia - similar level as Continental. They don't fly all year - I think they start again in May. The advantage of connecting in the USA is you need to clear immigration at the first point of entry so when you arrive into Orlando International it is much quicker coming from a domestic flight and you are out with your luggage into the car much quicker.
This is my personal experience. Not sure it helps.
Cathie