Video & Online Gaming: How to go about Building a Gaming PC?

Might be old, had this set-up since 2009

Currently these are the specs I have:
Model: Presario CQ62 Notebook PC
Processor: Intel (R) Celeron (R) CPU
900 @ 2.20GHz 2.19 GHz
RAM: 2 GB
System: 64-Bit Operating System

My system runs Window 7,

Curious on how to build a Gaming PC, any advice, price range; ect would be welcome.

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Minecraft won't close whatever i do?

I have tried forcing it to quit. Using task. Simple closing it. Logging off from my account. Shutting down laptop (which won't work unless mine craft is closed) simply disconnecting. All i have is a black frozen screen. I have waited over 5 hours! What now?! I have a MacBook Pro

How to make my Minecraft run smoothly?

I have a good computer. But my minecraft runs laggy. My computer has 4 gb ram but still it runs laggy. I tried lowering the video settings on minecraft but then minecraft got really bad pixelated but still did not solve the issue though it was clear due to lowest settings. If anyone can come up with solutions that would be really appreciated.

Long Minecraft adventure map?

I've been looking for a longish Minecraft adventure map (Note adventure and not Survival, one that'll take me a few hours to complete) for a while. Are there any long, beautiful looking Minecraft adventure maps with good stories you know about?

Minecraft not working/ updating on my windows vista PC?

I have Windows Vista on my laptop, and whenever I open the launcher and click play, it says it is updating, and the bar will quickly fill and restart as it would after the update, except it doesn't update, and it won't let me play it. I have tried deleting it and re installing it, which did nothing. I have been searching around and it seems as if no one else is having this problem, unless I'm searching for the wrong things.

Any help you could provide would be extremely helpful, thank you!