The number 1 way to keep your PC error free and running great is to not install anything you don't "need". This is easier said than done.
I try to play with all software that I am evaluating on a virtual machine. I try to install as little as possible to my actual system.
Another way I have kept my machine clean is with my Acronis True Image software that I purchased. It has a mode called Try&Decide. So, if I do want something on my actual machine, you fire up Try&Decide and it takes a snapshot of your machine. Then, you can install and play with whatever you want. At the end, you can simply tell Acronis to revert back and and it takes you right back where you were...with nothing new installed on your system. I've used that extensively to trash changes and it's worked very well. I tried "ONCE" to commit changes and had a real problem on my hands. So, from now on, if I want to commit changes..I revert back and simply complete the steps again without Try&Decide running.