Can I get by without FLASH?

reason for my question, my 21" iMac decided to blackout the screen 3 times in two days so I took it into the Genius Bar at Burlington. The very nice lady ran some tests that told us my hard drive was Okay so she installed Apple/s Anti_Malware and ran it. It showed two pieces of malware which she got rid of, how I don't know I just watched. She then installed it so I could use as necessary. Oh, I am running Yosemite 10.10.5. So I go home happy as a little pig power up for about 20 minutes when the screen goes black! So I run the Anti-Malware program and the only thing it shows is FLASH download program icon. Now when I try to delete it or move it to the trash NOTHING it will not move and there is heading under the file program to delete FLASH? So I go on my hard drive but only thing I can find for FLASH turns out to be an Alias which the machines says I cannot delete? Some other facts, I was using Firefox as a browser , it didn't happen while I was on the same sites.
If I can do without FLASH fine please inform me how to get rid of it Keeping in mind that I am an OLD guy who when he cuts a piece of wood three times it is still too short!

Thanks

via ehMac.ca http://ift.tt/1hsWkmI