I have been using my Acer Aspire 5742G notebook for over two years now, and recently had to restore it to factory settings by recovering the OS and Applications using the eRecovery process. This was in early April 2013, and I have been keeping the notebook updated with the latest Windows critical updates and use the latest browser versions too (IE10, FF22, Chrome27). Have noticed that of late the notebook abruptly freezes for about 1-2 minutes and then returns to normalcy. I cleared the cache in browsers, have uninstalled all unwanted programs installed during the OS recovery process (using hidden partition), but this hasn't changed anything. Even defragmenting hasn't helped so wonder which program / any hardware issue is causing this.
Recently I also downloaded and ran Defraggler, a free tool to defragment a HDD. When I used the Analyse option it showed 18% defragmentation, and after defragmenting thru Defraggler (it ran for about an hour), it still showed 16% fragmentation. Also, when I use the Windows' default Defragmentation too, I noticed that the hidden partition of about 13Gb, which stores the OS and other programs shipped with the notebook, shows a fragmentation of 22% but am not able to run the Defragmentation process on this partition.
So, would like to know what may be causing the system freeze, and how I can sort out the defragmentation issue on C: drive, which may be the culprit.