now displays two page spreads across width of window, but can be kind of short. Also worked on the focus issues a bit after the dialog box

main.py

@@ -2,7 +2,7 @@ from tkinter import *
 from tkinter import filedialog
 from zipfile import ZipFile as zf
 from PIL import Image, ImageTk
-import io,os, pickle
+import io, os, pickle
 
 class MangaReader:
     def __init__(self, master):
@@ -19,7 +19,6 @@ class MangaReader:
 
         master.title("Manga Reader")
 
-
         #Load settings 
         settingLoad = pickle.load(open('manga.p', 'rb'))
         self.dir = settingLoad['directory']
@@ -71,15 +70,20 @@ class MangaReader:
         self.master.bind(self.quitKey, self.shutdown) 
         self.master.bind(self.openKey, self.open_menu)
 
+        #watch the 'x' button for window close
         master.protocol('WM_DELETE_WINDOW', self.shutdown)
 
-    def open_menu(self):
+
+    def open_menu(self, *event):
         # file dialog. reset page counts, call display Maanga passing in starting values
         if self.dir == 'None':
             mangaFile = filedialog.askopenfilename(initialdir = "/home/dan/Desktop/")
         else:
             mangaFile = filedialog.askopenfilename(initialdir = self.dir)
+        if mangaFile != '': 
             self.file = mangaFile
+        else :
+            self.panel.focus_force()
         if self.file != '':
             self.page = 0
             self.total = 0
@@ -110,6 +114,13 @@ class MangaReader:
             hpercent = (hsize / float(im.size[1]))
             widthsize = int((float(im.size[0] * float(hpercent))))
 
+            if widthsize > self.master.winfo_width():
+                 widthsize = self.master.winfo_width()
+                 #widthsize = im.size[0]
+                 wpercent = (widthsize / float(im.size[0]))
+                 hsize = int((float(im.size[1]) * float(wpercent))) 
+                # self.master.config(width=widthsize)
+
             im = im.resize((widthsize, hsize), Image.ANTIALIAS)
             #convert to tkImage and update the on screen image.
             self.img = ImageTk.PhotoImage(im)
@@ -117,8 +128,7 @@ class MangaReader:
             #finally update the current page count
             self.pgcount.configure(text=str(pg+1) + " of " + str(self.total))
 
-            self.panel.focus_set()
-            self.master.config(width=wsize)
+            self.panel.focus_force()
 
     def nextPage(self, event):
         self.page = self.page + 1