Everyone is trying to help you. Here are some issues that are making it more difficult:
- We do not know whether the hardware is reliable or whether it has a defect or a hardware fault of some kind:
- Could that be why it "stuck like a terminal" with Ubuntu?
- Could that explain why you only 3 Gbytes "useable" RAM instead of the full installed amount?
- We do not know why it "stuck like a terminal" with Ubuntu.
- We do not know whether the problem happens only with Ubuntu.
- That makes it hard to recommend another distro that can solve it. We do not know whether the same issue will appear there.
- My guess is that if it happens with Ubuntu, it will happen with other distros too.
- We do not know why it has only 3 Gbytes of useable RAM.
- We know you have a 64-bit computer.
- 32-bit versions of Windows are limited to 3 Gbytes of RAM. That may explain why you were being asked a lot of 32-bit questions. It is understandable.
- If a 64-bit computer cannot use all 4 or 8 Gbytes of RAM installed, then there must be some kind of problem or issue.
- It is very unlikely to be the choice of Linux distro.
- If you boot a current live 64-bit Linux installer from a USB drive and it shows that you have only 3 Gbytes RAM when more is installed, then there is a problem.
In my opinion, you need to determine whether you have reliable hardware first. Until you know that your computer is not broken, it is hard to choose a distro that will work.
I would create and boot a USB drive and test using the live Linux on that.