Instant Messenger (AOL)

My son would like to upload AOL Instant Messenger.  My concern is receiving virus' through this system.  Is Dell supportive of IM, are there various things we should do in advance to safeguard our computer before loading this system?  We are not computer literate and do not have the time or patience, nor do we use our home computer often, to know how to best handle or avoid virus'.  So if anyone can provide direction keep in mind we're pretty green. Thanks