when you open the game, 1st go to the options/settings, then set the video resolution/video settings>resolution to 720p, or 1280x720. In the settings there may be a option to reomve full screen too, you can do that too...
Does it have a graphics card? If so which one? If not then your running on integrated graphics it doesn't matter if you have an i5 games wont run well.
What's the model of your notebook? Some notebooks have a seperate graphic card, but some don't have graphic card. These games won't run properly if you have an integrated graphic processor, like the Intel HD Graphics 4000 (poor) .
If you can tell me the laptop model, I can check whether it has a seprate graphic card or integrated graphics
For Example: HP 15-P001TX Notebook with Nvidia 830M Gaming Graphics (Good Seperate Gaming Graphics)
AND
Dell Inspiron 3537 Laptop with Intel Graphics 4400 (Normal graphics, not & poor for gaming)
P.S.-I have a feeling that the above given Dell laptop(inpiron 3537) is yours, just check? Yhis one has a core i5 and 6gb ram too.)
when you open the game, 1st go to the options/settings, then set the video resolution/video settings>resolution to 720p, or 1280x720. In the settings there may be a option to reomve full screen too, you can do that too...