@Jade Aislin - You'd asked about changing the appearance of the comments field:
Originally Posted by JimmXinu
The comments field in calibre's metadata? I'm just shoving plain text into that w/o HTML. calibre's adding a bit of HTML around each paragraph with class="description". I wonder if one could change the def of "description" somewhere.
I happened to find where this is set while looking for something else.
The general answer is in Customizing calibre, Overriding icons, templates, etcetera
First, find your calibre config dir by doing Prefs->Misc->Open calibre conf dir. Go into resources, make a directory templates.
Then, copy C:\Program Files (x86)\Calibre2\resources\templates\book_details.cs s (or equivalent) to the templates dir you just made.
Edit your new book_details.css file and add:
...or whatever size you like.
I believe that will do it for you.