I have an older iMac running mojave 10.14.6g
I suspect this computer is infected with malware. Runs very slowly and seems to not have as much memory, 8GB, as it should. I tried upgrading to the new system but it got stuck. Now if I try to upgrade it says it doesn't have room on the hard drive because the first try is still there partially installed.
I want to get a new computer. But if I just load the new computer from the old I'll be moving the malware and the stuck operating system. Mostly I care about my music, Apple Music with thousands of my personal music and music from Apple Music, and my photos.
What is the best advice for doing this. Should I take my computer to the Apple Store when I buy a new computer and try to get them to do it for me? Should I visit the Genius Bar?
Thanks for any advice.