Does changing Linux desktop environment can speed up its performance

I want some help in fixing the desktop environment of Linux pc. I am having a Ubuntu based system, which is not working well. I am having around 2GB ram on the same. But sometime it respond very slow and I am quiet sure that issue is with the UI. There are lot of things I had added to make it look better. Now I am planing to shift to some basic UI where it can work well.

Yes you can do that. You can replace the current one with any lightweight UI where you get all basic things you want. That would be the fastest way of speeding up your OS without making any major changes. Before moving ahead just try to copy your files. One of most lightweight UI that I had seen is LXDE. It is having limited things and it works very fast. Does not require much ram.

You can use Mate. This not only easy but it is also quiet thin and very similar to Windows. Where you get a start menu and you also get some required programs on the same. You can download this and install it on your existing Ubuntu system. And if you want to simplify the UI more then you can try using OpenBox. It is a simple to use utility to customize the UI of Linux based system.