This week's book giveaway is in the OCPJP forum. We're giving away four copies of OCA/OCP Java SE 7 Programmer I & II Study Guide and have Kathy Sierra & Bert Bates on-line! See this thread for details.
Well Spring will use AOP to be able to provide Transactions and Security, but you won't have to implement the AOP code yourself. Just declare a bean of transactionManager. Spring has many TransactionManager classes for any environment. Then use Spring security.
Now if you choose to configure it all with xml, then you will need to know the AOP expression language. If you use Annotations, my preference, then you have less typing and don't have to know the AOP expression language. Although it would be beneficial to understand how to read the expression language at some point.