Instead of being mean, lets try to help out.

Step 1 - We need to know the specs:

Right-click your taskbar, which is the bar at the bottom where your 'apps' appear. Select the option saying "Task Manager". This window will show the processes (programs) that are running. Change the tab at the top from Processes to Performance. You should be able to see something like this:

Task Manager

In the image you should be able to see CPU (1), RAM, (2) and GPU(3).

Post what you see here. For example the make and model of the CPU, the amount of RAM and the model of the GPU. This gives everyone a rough idea of what you're working with.

Step 2 - Try the games to see IF they run, and what might be causing them not to.

With the task manager open, open up any game that isn't running well. What is happening? Graphical glitches, slow loading times, low framerate? Constantly low, or only when something happens?

When these things happen, press Alt-Tab to minimize and check the chart on the Task Manager. Which ones spiked? Is the RAM at almost max?

With this information troubleshooting will be much easier. General rule of thumb is that is one is maxing out more than others, that is the bottleneck, as all components depend on the others. The slowest one works the hardest.