Fraser Fir are really nice because they smell so lovely as well as not dropping needles, but don't buy it from Homebase - support your local Christmas Tree Farmer if you can. Sorry if you live in the middle of a big city though - then I guess it's a bit difficult!
It is good to buy local but most Fraser fir are grown in Scotland so unless you live there it may be difficult. Ones at Hombase are from the UK so at least you can buy British.