Definately Gulf Air. They are far supperior in every respect, in my opinion. I say this because I flew both airlines from FRA-BOM-FRA within 4 months of each other and I can say that the food is better on Emirates but that is all that is better than Gulf Air. EK's crew are one of the rudest I have ever been served by, plus the enterainment system was not working proprly on 3 out of the 4 flights on EK. GF is better with the crew being extremly freindly and the entertainment system on the A330 is excellent. I hope you have nice trip and please write a trip report.
Once again this is my opinion, others might find EK better!!