error messages and frequent hang's...

some of the programs i installed recently hangs and/or don't run instead show error messages? what could be the possible cause/s of this?

my pc also hang's once in a while whenever i try to shut it down... lots of dialog boxes are popping before i could shut down the pc... it says that a certain program/process is not responding... what could be the problem?

disclaimer: i not that expert in computers but i'm enthusiastic to learn

We will tell you more after you tell us more...
Computer brand and model, os, age, text of errors presented, programs installed that seemed to cause this... Send us the workding of the error notice "certain/process is not responding..."
From what you have told us thus far, it could be anything... hardware error, driver error, software install error, or infestation.

You do not have to be an expert to know:

1. To get help with an error message, you need to tell us what the error message says.
2. Something that started up when you booted and has been running in the background won't shut down. This could be a legitimate process or malware. Those 'pop-up boxes' are coming from the Task Manager and are telling you WHAT won't shut down.

Make note of what it says and tell us if you want help.