Problem with computer

Hi, I have had my laptop for 2 years now and switched from Windows vista to Windows 7 Home premium. I recently downloaded Adobe after effects 32-bit for my laptop. i have been rendering videos for my friends for our animation project for our GCSE's at school. a couple of days ago i had problems with programs stop responding like dwm.exe java.exe and also had problems with my screen flickering like mad. But today has been the worst day, me and my friend where doing some rendering and then my computer just shut down. It hadn't over-heated or anything but it had been lagging while rendering. The cpu had been at 97 - 100% for about 2hours. we started the computer back up and it was fine. We started to render it afain but it shut down again but it still hadn't over heated. for the second time we turned it on and it took about 20 - 30 minutes to start up and when we did it again it froze the computer and then it started flickering again saying programs had stopped responding and stuff but they where still running. We have also had problems copying files over to our HDD and 10mb files would take 40 mins to send across. Would anyone help solve our problem on why it is doing this please?

 

First question: did the 'switch' from Vista to W7HP involve a format and fresh install or was it an upgrade?

 

it was a complete reformat.I updated to win7 about half a year ago

 

Ok, a clean install should mean this is fixable, if it's a Windows problem

You made a point of saying After Effects was 32-bit, does this imply that you have 64-bit W7? Have you updated to Service Pack 1 yet?

What security software do you have installed, and which version(s)?

Some of your symptoms make me think malware (dwm.exe, java.exe), others read like graphics drivers (dwm.exe again and the screen flickering), I also think there could be some data corruption.

When did the laptop start misbehaving?

 

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4 days ago i went to install service pack1 but it failed so i didn't try it again due to it took about 3 hours.

It started about a week ago when i downloaded steam from their website.
when i installed it kaspersky found a trojan in steam.exe
i un-installed it and re downloaded it but no trojan was found.
2 hours later i was using internet explorer 9 and wanted to view a website on imdb.com to see when fast five was out and it stopped responding. and said eula.exe was missing. so i went on google chrome to watch some youtube videos and it kept lagging and then my computer froze and the sound went glitchy and the cpu went to 100% so i restarted the computer and it was a bit better. I haven't used my computer since then.

 

One way to get a high % success rate with any major SP is to download the network (full) package, go offline, then disable (or better, uninstall and reinstall post-update) any real time Antivirus/Antimalware programs. Then run the SP installer.

Given the Eula.exe thing and the problems from there onwards, I'm gonna suggest you head over to the Malware forum; read carefully and follow implicitly the instructions given the the Read and Run post here. We need to be sure the machine is clean - this might just cure most, if not all, the recent problems you've described.