How to Subdivide QuickBooks Register?

I'm a newb here.  By no means am I a QuickBooks expert.  A friend gave me QB 2008 long ago to replace the paper/pencil register on my personal checking account.  I have successfully used it for its checkbook register and nothing else.  So now I have amassed approximately 14yrs of register entries and it balances perfectly every month.  I noticed the QB file in my hard drive is ever-growing, and approaching 100Mb, which concerns me.  It doesn't seem logical for me to continue amassing years of register entries in the same file, while my PC disk space is continually eaten up.  I'm curious what folks typically do in terms of subdividing and/or archiving the QB file.  I would like to retain the historical entries in case I ever need to review them; i.e., I don't want to just delete them.  Is there a way to archive those old entries?  Can the register be subdivided somehow?  What are the "best practices" for handling this situation?