This week's book giveaway is in the OCAJP 8 forum. We're giving away four copies of OCA Java SE 8 Programmer I Study Guide and have Edward Finegan & Robert Liguori on-line! See this thread for details.
I would not recommend JBoss AS5 whose development has stopped years back. Instead use the latest JBoss AS 7.1.x releases.
Anyway, your question is way too vague to get an useful answer. Typically, you should start deploying the application to the new server and start looking into each error/issue that you run into (if any).