That’s not too bad
1.9.4.2 isnt that old and many people have held at 1.9 something
You can do most of bringing it back with settings once youve changed to 2.5
The new settings (in customiser) are a bit of a jumble and sometimes you have to scroll down through them to find a useful one off the bottom of the page
If you want the right sidebar widget title background to look the same as you have there, check out