Fresh install of Win7, yet very unresponsive and slow?

I attempted to dual boot Mac OS X (failed!) so as a result, I had to reformat my full hard drive and reinstall Windows 7 (I have lost my backup image).

I downloaded a copy of Windows 7 Home Premium 64bit from the internet, burned to a disk and had issues (hanging on expanding windows).
So I burned another disk and it worked! Installed without a hitch and I used to activation code printed on the bottom of my computer.

But now, I have an unresponsive computer that is very slow. It takes quite a while to boot and often becomes unrespnsive when I try to do anything, this is making installing drivers very hard.

I have no clue why this is happening, but I have suspitions that my hard drive is broken.

Installing drivers and software is becoming hard and often fails.
I have flashed my BIOS with the correct BIOS from the Acer Support website and still had no luck.

Has anyone got any clue what is wrong?

Computer: Acer Aspire 5742
i3-370M processor
Intel HD Graphics
4GB DDR3 RAM
250GB HDD

I would Check the hard drive with the manufacturer's diagnostic tools.
Hard Drive Diagnostics Tools and Utilities (Storage) - TACKtech Corp.
HD Diagnostic

   Information

We always assume you have made your Recovery Disks using the OEM manufacturer's app the first day you had your new PC.
& made the Startup Repair CD.
startup repair disc-create

You can Order Acer recovery disks from here:
https://secure.tx.acer.com/RCDB/Main.aspx?brand=acer

Thanks for the fast reply!
I'll try what you have said.

But the Acer recovery disk website doesn't recongnise my serial number or SNID. Strange?

The full model number off my computer is: 5742-374G25Mnkk
Now a search on the Acer website shows nothing.

Was this a legit Windows 7 disc image downloaded from a Microsoft website?

Follow these steps to get a perfect clean reinstall of factory OEM: Reinstalling Windows 7

Best to borrow an installer from a friend even if you have to unlock all versions to reinstall your licensed version with the Product Key on the COA sticker.

If forced to download from web, search for "official Win7 ISO downloads" to find the clean copies at Digital Life.

Once you've got a perfect install, if problems persist work through these troubleshooting steps

It was a copy downloaded from Digital Life.

I made a system restore when I first booted, so I'll restore it and just install my wireless driver and then allow windows to install the rest.

The problem I am having is most drivers wont install. The install fails.

For example when allowing windows to install a driver for my Intel HD graphics, I get this message:

'windows found driver software for your device but encounted an error when attempting to install it.
This operation returned because the timeout period experied'

Are these drivers which are missing in the Device manager?

Win7 is driver-complete in the installer, with newer arriving quickly via optional Windows Updates.

I would not change out any drivers given by the installer or optional Updates unless performance points to a specific driver causing problems. This is not XP.

Well they aren't working, so I'm assuming they're missing.

There are two drivers missing, one for my graphics and one for my LAN.

Always update drivers from the OEM manufacturer's website.

You can download drivers for Acer Aspire 5742 here:
Acer Support: Downloads & Support Documents - Notebook / Aspire / Aspire 5742Z

Thanks for your help but I actually haven't a clue what is wrong.

That website above is the one I used to get the drivers and it says on the website that they are the drivers that aren't included in Windows 7.

The problem is, the drivers aren't the problem it is trying to install the drivers. Every installation fails and the computer is still unresponsive. So the install can't be correct to start with.