The answer is no, Microsoft Security Essentials wont protect you. Microsoft has stopped supporting Windows 7 and is not sending out any more security patches which mean your antivirus software will stop catching any new virus after January 14. You will need to buy a new laptop. I dont recommend upgrading your current one due to its age. After five years hardware can begin to fail. And you'll need at least 8 gigabytes of memory to run windows 10. If your laptop doesn't have it then I'm not sure you want to invest any money or effort into upgrading it.
Judy, you asked your question on a public forum, and isn't clear what your question is. Why don't you just call Santa Rosa Computers and ask Tran?
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