Apache OpenOffice is basically a clone of Microsoft Office 365, it has all the very same apps and components, it can open and save all MS Office document formats, it's actively supported, it's available for all the popular platforms (Windows/linux/Android/OSX/etc), it's fully opensource, and it's completely free.
To be honest, I seriously wonder why any person (or any company) would ever pay for MS Office - and for all of Microsoft's various arbitrary licenses and restrictions and subscription periods and usage limitations - over and over again, lol.
AVG Antivirus is free for 30 days and will cost you nothing more than an email address to register/(re)activate every 365 days.
It's often my preference on Win7/Win8 systems because - unlike the free/trial versions of Avast! and McAfee and Kaspersky - it can be configured to quietly do it's automated chores on the System Tray and never bother you in any way unless it happens to detect a threat.
If a computer comes with free software then use the free software until it's no longer free or no longer worth using. Then remove it and install free (and better!) alternatives. It's not an important consideration when purchasing a system - in fact, 99% of us would do better by uninstalling whatever "value bundled" bloatware the manufacturers pre-install onto every system.
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