Laptop developed some bad quirks - Windows 8.1

[Imago23]

After some time my private laptop picked up some quirks I can't figure out, what is causing them. I don't know, if some of them are related though.

Minor problems:
For example after a restart the first start of "Start Menu" is always extremely slow, sometimes taking up to one minute. After that it becomes better.
The startup of eclipse is also slow, but I think it is ok for that program to be slow, since eclipse is always a monster in size and eating resources.

Major:
After startup and logging in, my laptop always seems incredible busy: Going after the Task Manager Disc Usage is almost always 100%, also the CPU usage is very high.
Most of the time programs related to the System cause this, namely: Service Host (Local System), System, Service Host: Local System (Network restricted)   
At all 10 different versions of Service Host are listed and I do wonder, if they are all needed.
After maybe half an hour it calms down, Disc Usage is almost 0% as expected, if there is no program running.
My CPU however seems still to be occupied easily by a browser or opening pdf files or word files..

Critical:
Another problem is related to Google Chrome: I can login to hotmail.com, however I cannot "log out" or view e-mails, cause they are not displayed. I can click on the respective Links, however then either nothing happens, or in case of the emails, a white page is presented, where the email content is supposed to be.
I also noticed in google chrome: I cannot watch a certain live stream of: http://www.lolesports.com/en_US/
Google chrome first sent me to a black screen, now redirects me to http://www.lolesports.com/en_GB/
I also cannot use freenet.de

This behavior is creepy, since hotmail.com works in a Chrome Browser of a different Laptop (mine at work)
For now I can bypass these problems using a different browser, Firefox.

I tried reinstalling google chrome, emptying cache, and ran several scans of avast and anti-malware bytes. avast (as always) didn't find anything, anti-malware bytes had a couple of hits, they are taken care of, however the problem still persists.
System Event Log also seems to be clean, I found nothing not abnormal there. Task Manager also lists no problems, that should not be running.

I really hope someone can help me, I am very thankful and delighted for any constructive answer. Thanks in advance.

Laptop specs:
Lenovo G50-70
OS: Windows 8.1
Processor: Intel (R) Pentium(R) 35580.U @ 1.70GHz 1.70GHz
System Type: 64-bit operating System, x64-based processor
Installed Memory RAM 4GB

[SuperDave]

Hello and welcome to Computer Hope Forum. My name is Dave. I will be helping you out with your particular problem on your computer.

1. I will be working on your Malware issues. This may or may not solve other issues you have with your machine.
2. The fixes are specific to your problem and should only be used for this issue on this machine.
3. If you don't know or understand something, please don't hesitate to ask.
4. Please DO NOT run any other tools or scans while I am helping you.
5. It is important that you reply to this thread. Do not start a new topic.
6. Your security programs may give warnings for some of the tools I will ask you to use. Be assured, any links I give are safe.
7. Absence of symptoms does not mean that everything is clear.

If you can't access the internet with your infected computer you will have to download and transfer any programs to the computer you're using now and transfer them to the infected computer with a CD-RW or a USB storage device. I prefer a CD because a storage device can get infected. If you use a storage device hold the shift key down while inserting the USB storage device for about 10 secs. You will also have to transfer the logs you receive back to the good computer using the same method until we can get the computer back on-line.
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Let's run some scan to see what going on with that computer.

Please download AdwCleaner by Xplode onto your Desktop.

Before starting AdwCleaner, close all open programs and internet browsers, then double-click on the AdwCleaner icon.



If Windows prompts you as to whether or not you wish to run AdwCleaner, please allow it to run.
When the AdwCleaner program will open, click on the Scan button as shown below.



AdwCleaner will now start to search for malicious files that may be installed on your computer.
To remove the files that were detected in the previous step, please click on the Clean button.



AdwCleaner will now prompt you to save any open files or data as the program will need to reboot the computer. Please do so and then click on the OK button. AdwCleaner will now delete all detected adware from your computer. When it is done it will display an alert that explains what PUPs (Potentially Unwanted Programs) and Adware are. Please read through this information and then press the OK button. You will now be presented with an alert that states AdwCleaner needs to reboot your computer.
Please click on the OK button to allow AdwCleaner reboot your computer.A log will be produced. Please copy and paste this log in your next reply.
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Please download Malwarebytes Anti-Malware from here.
Double Click mbam-setup.exe to install the application.

• It should update automatically if the computer is connected to the internet.
• Click on Threat Scan and click on Scan Now.
  
• The scan may take some time to finish,so please be patient.
• When the scan is complete make sure all the infections have "quarantine" selected in the Action box.
  
• Click on "Apply actions" You may be asked to Restart your computer to completely remove the infections.
  
• When disinfection is completed you can click on "Copy to Clipboard".
  
• Paste the log in you next reply (CTRL+ V)

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Please download Junkware Removal Tool to your desktop.

•Warning! Once the scan is complete JRT will shut down your browser with NO warning.

•Shut down your protection software now to avoid potential conflicts.

•Temporarily disable your Antivirus and any Antispyware real time protection before performing a scan. Click this link to see a list of security programs that should be disabled and how to disable them.

•Run the tool by double-clicking it. If you are using Windows Vista or Windows 7, right-click JRT and select Run as Administrator

•The tool will open and start scanning your system.

•Please be patient as this can take a while to complete depending on your system's specifications.

•On completion, a log (JRT.txt) is saved to your desktop and will automatically open.

•Copy and Paste the JRT.txt log into your next message.
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Download Security Check by screen317 from one of the following links and save it to your desktop.

Link 1
Link 2

* Double-click Security Check.bat
* Follow the on-screen instructions inside of the black box.
* A Notepad document should open automatically called checkup.txt
* Post the contents of that document in your next reply.

Note: If a security program requests permission from dig.exe to access the Internet, allow it to do so.