hey..
1. carrying tapes with you is fine...although it might take up alot of luggage space. There are VHS outlets available and u can rent videos as well as buy a video player.
2. converters sold in qatar are safe provided u buy them from the right outlet and they are definitely cheaper than the ones u found at Radio Shack.
3. U can bring anything in your shipment as long as it does not contain alcohol or pork.
4. I don't know if you can bring pork in..I haven't tried!!
5. You can get a christmas tree here and decorations...but u might want to bring a few nice ones along with you just to remind you of home!!!

hope u have a safe trip here...