Regular Servers Crashs

So I Wanted To Play With My Friend MC And Building a RPG Town With Him, But Unfortunealy Since He Has Windows 10 And I Have 7 It Crashes.
How Do I Know?: We Thinked Of All The Solutions And This WAS The Only Solution We Could Of Thinked Of.
Here's The Logs Of The Server
The Server Desgined From: Mojang
P.S I Don't Know What The Crash Log Means So If This a Bug Or Something With My Computer Please Tell.