Is it safe to tick the sub options under ‘Advanced’ in CCleaner?
As Jeffery said they are pretty much all safe although certain options do have certain drawbacks!
For example cleaning the Menu Order cache means that the entire Startmenu will be organized alphabetically next time you start your system - I myself prefer that in the same way but maybe you do have some customized order...
Window Size and Location cache will obviously delete what it says. Any window or application you resized to cover a specific portion of your screen will be back to its default. If you are experiencing difficulties with your system it might be a good idea to uncheck Memory Dumps and Windows Log Files under the System options because they could contain helpful informations.
I could go on but you probably get the idea.
My personal approach when I started using CCleaner was to select everything, click on analyze and then double-click on each individual result to see a detailed list of files and entries which are going to be removed.
Read CCleaner - Advanced Windows files for a more in-depth description of what each of these items do.
To me, yes - they all seem safe to delete. Wiping free space however, will take a draconian amount of time.