Image Resize Filter not working with WYSIWYG + CKeditor?
For re-sizing of images instead of using Image Resize filter you colud use the feature of drupal 7 itself ie by setting up an File Type for your image.

You could set up a File type you should go to Configuration -> Media -> File types -> Manage Display 

There are basically 6 types of image file type that you could use


Link 
Default
Preview
Large
Original 
Small


These are the default file type that you can select and are there with there default values so we could override the default values by our own values and could use that file type for uploading our own images of particular size.