Boot time can usually be affected by the scan processes on enable option, however I believe that is disabled by default... Just out of curiosity could you check the setting - go into VSE console and double-click on-access scanner. The option should be listed under the general tab - is it off? Also, is this a fresh install or upgrade, and is it standalone or managed by ePO?
No problem at all - let us know if it helps! A quick further note - as you are not scanning processes on enable, it is recommended that processes are covered in your on-demand scan settings. Sorry, forgot to mention that!
Another thing that can cause boot delays is if you in the habit of storing emails in your email client's Inbox. I suggest creating special folders for storage and keeping Inboxes clear.