OK, I see. Well, I don't know how good you are at soldering, but here's a few tips:
* Wait for the iron to heat up. Use some solder to melt a thin layer on the first 5-7 mm of the tip. More isn't a problem, you just waste some solder, no big deal.
* Heat the joints properly before applying solder. Molten solder will go towards the heat source!
* Don't move the joint until the solder has turned solid again. The joint should be hollow (unless you've applied too much solder
* To de-solder, use a manual suction pump, made for this purpose. If the Maplins attendants are worth their salt, they can advise you which one would do the job and don't cost a fortune. Heat the joint, then suck away as much solder as you can. Sometimes it helps to add just a bit of fresh solder. Wiggle the component loose gently while heating the pins. But most of all: take your time!