I think this very useful script maybe improved if it can run by right clicking a folder without selection window.
There is also a typo concerning "resized" folder which results in original files being overwritten.
So here is my suggestion:
===============================

if hash zenity 2>/dev/null; then
if hash mogrify 2>/dev/null; then
loc=$(${ZENITY} --file-selection --title="Select a Folder" --directory)
cd $loc
pwd
mkdir $loc/resized/
cp $loc/* $loc/resized/
cd resized
size=$(zenity --title "New Size" --entry --text "Please enter the new size as WxH")
type=$(zenity --title "File Type" --entry --text "Please enter type of files to resize")
mogrify -resize $size! *.$type | ( zenity --width=400 --height=100 --progress --title="Please wait until OK..." --percentage=1)
else
echo "Please install the dependencies imagemagick and zenity"
exit 0;
fi
fi

what theme did You use ?

New wave on jaunty as far as my memory is right

kramp thanks for the advice no the script in changed as you have suggested, still more improvements and suggestions is always welcomed so the script , becomes full stable
and the user is advice to run the script as a root, but as you have mentioned they might not have permissions.

in your script:

echo "Installing the dependcies"
sudo apt-get install imagemagick
sudo apt-get install zenity

You should change these lines, and just display an error, for the following reasons:
- the user may not have the sudoers rights
- your script might work on other packages systems

Or at least ask the user to confirm the dependencies install