If your window is cracked but still in one piece , you can buy 'shrink wrap' window insulation that is temporary

http://www.walmart.com/ip/17133826?wmlspartner=wlpa&selectedSellerId=0&adid=22222222227016740459&wl0=&wl1=g&wl2=c&wl3=40872617312&wl4=&wl5=pla&wl6=78765400352&veh=sem

You can also bubble wrap your window! If it has a huge hole, you will need to insulate it well . You can also get temporary paper shades:

http://www.bedbathandbeyond.com/store/product/redi-shade-paper-window-shades/1010849217?skuId=10849217&mcid=PS_googlepla_nonbrand_windowtreatments_&adpos=1o5&creative=43742659789&device=c&matchtype=&network=g&gclid=CKaC_LarvcoCFcGRHwodEqgDTA

As for your decor, you have a LOT of brown. You need to break it up with color. I would suggest teal and orange Ikat pillows for your couch, fun teal drapes and some complementary storage bins for your little ones toys. Accent walls break up the flow of the room ( making it look smaller) . Add some art on the walls to cheer it up.

Here are some ideas:

And an ottoman for toys and extra seating. Could also double as a coffee table- also at Wayfair.com:

A fun piece of affordable art at Etsy: