Is this PC infected?

My mother-in-law asked me to look at her PC. It’s extremely slow. The hard drive has 31.8 GB total space but only 2.73 GB of space is left. I think this could be a major cause of the slowness.

I thought I’d also do some checks for malware. I ran Microsoft Essentials which said the PC was clean. I’ve just completed a Malwarebytes Anti-Malware (MBAM) and it’s found 21 items. I would be obliged if someone could look at the log and advise (1) how serious the items are and if (2) I ought to the Majorgeeks full malware Read & Run Me.

I attach the MBAM log.

MBAM wanted to quarantine all 21 items therefore I applied its recommended action. MBAM reported it successfully completed all of them.

I’ve noticed that since I restarted the PC as requested by MBAM the computer is a little faster.