Let me start by stating that I may be somewhat biased as my wife hails from Bogota and we go there at least every Christmas to see the family.
With that out of the way, down to Business, at least as far as Avianca is concerned.
Until a few years ago, Avianca were operating a direct non-stop flight from LHR to BOG. Both of us were members of their FF program and we thought it was great. 2 round trips in coach gave you enough miles to upgrade yourself into Business (round trip).
The service was great and the food was nice although as already commented the product was a little old. I don't know how it is now as we haven't flown with them since they fouled up our flights one Christmas.
As for Bogota itself, it is an amazing place. People are generally very friendly and sure there are places you wouldn't go, just like there are parts of London I wouldn't want to wander into after dark.
They Colombian's love their shopping centres (malls?), some of the best are "Atlantis" (in which the Bogota Hard Rock Cafe is located) and "Andino".
The gold musuem is a true wonder to behold and of course you'll find lots of shops with Emeralds as well. You may also want to take the cable car up to Montserrate (not too sure on the spelling) where a church overlooks the city and gives a breathtaking view.
Oh yeah, if you need cash, your best bet are the ATMs from either Servibanca (can't miss them, they're bright green) or Bancafe. These always seem to work, whereas with a lot of the others, their international comms seem rather shaky (at least where our UK based accounts are concerned).
Finally, do use sunscreen and be aware that with the altitude (something like 2,600 metres above sea level) you will get breathless if you do things too fast.
Enjoy!