I currently have other storage around 90GB on a 120GB internal drive so pretty much all of it. I have optimised to iCloud and deleted all large extra files and documents etc. However, on the omnidisksweeper it is showing there is 20gb just in updates and 13gb on system but I am unsure what I can delete. Any help will be appreciated!
I woudn't be concerned too much with those two since they are only 33 gigs total. The 90 GB space should be of more concern. I suggest you get Daisy Disk or Grand Perspective to give you a color graphical mapping of your disk drive. These color maps make it easy to see what is hogging your disk drive. Daisey Disk, if obtained from developers site has a free trial. Grand Perspective is free. I'm not familar with omnidisksweeper.