They might not be able to as it would be off-topic. Not sure.
My advice would be just join a guild as soon as possible I luckily got in a nice one with quite a few experienced ppl. They're very patient with all my noobish questions
Just not had much time to play recently
Can I use those characters in different campaigns?
Yes, and bringing 7 heroes along to help you with factions / prophecies makes the entire thing so much easier.
Once you get a hang of how to use heroes abit you'll want to head over to http://www.gwpvx.com/PvX_wiki or guildwarsguru.com to look up a decent "heroway" build that suits your playstyle.
Heroway basically means that you're the only player in the party, the remaining characters are all AI heroes.
And as always, if you need help don't hesitate to ask ingame