WordPress UPDATE

I would like to ask somebody for help. I am trying to update my wordpress since I received they are already 2 upgrades from my older version. I want to update to .4.4.1. version but my both laptops always showing me the window with: “Could not copy files. You may have run out of the disc space. Instalation failed”
What is not true. I have space on my disc and I deleted a lot of stuff just because of this and it didn’t help.
Also I tried pluggins like dropbox but instalation didnt work. I am not sure why I can’t also backup my database.
Can somebody help what to do? Since I cant add any more pictures on my blog and I think is the problem with wordpress version.
Thanks a lot
Alex
aholcbarova@gmail.com
This is my blog:
http://www.ruletheworld.guru