Windows Update taking ages and using 100% CPU

Hi peeps,
Never have I done a forum where I am asking the questions but this has baffled me and I can't get an answer anywhere, please help me!!!

one of my laptops is a acer 5315 and has had windows 7 home premium 64 on it for a fews years now with no probs but I always do a fresh install ever other year so I can get rid of the temp files and rubbish that on it, I don't use unnecessary software and have the basic software (ie + plug ins), office 2010 and Kaspersky for my antivirus, I have no documents on it apart from favourites and if I can run programmes from my NAS hard drive I do. anyway I put a fresh clean windows home pre 64 from Microsoft's website so is the latest iso and have nothing plugged into it and had no problems including connecting to the internet and activating my genuine windows key. I then get onto updating my computer and the problems start. It took about 45 minutes to check and it took up the 100% cpu while checking, making the laptop useless for anything else, it then came back with every update windows realised for windows 7 including SP1 which it is already has. I then got one of my older iso disks and used that one to make sure there was nothing wrong with the newer one and the same happened. So onto google and people were saying it could be a virus but it isn't as Kaspersky scans everythings on all computers and on the NAS so nothing can get in. Yes I know I can just not update it but I would prefer to have the updates if possible. I then unplugged all hardware inside that I could get too (wifi, modem, lan, webcam and battery) and done another clean install and still have the problem. I then looked at my other computers and none of them do this 45 minute checking for updates and none of them spike anywhere above 70%.

I then did another clean install but 32 bit as some results have suggested but still not changing, no viruses so I have got the right hump now!!!

So while that was checking I used one of my empty partitions on my Compaq laptop (which has dual boot with xp, windows 7, windows 8.1 and windows 10) and put a fresh clean of windows 7 32 on the empty partition and I couldn't believe it, it done it on that one too!! I went back on the other operating systems on my Compaq and none of them spiked and checked updates in under a minute.

So why i'm confused is: it can't be a hardware issue as two different laptops do it, software wise I have done 32 and 64 using the original disk when windows 7 came out, windows 7 sp1 disk I had on file and windows 7 sp1 media refresh from Microsoft website and I even used xp on the acer one and had no problems with it.

Please help me as I don't know what to do apart from throwing them out the window.

sorry used the wrong headline for this thread, please help!!

Weird. I have no consolation for you apart from the fact that I guess i'm not going crazy thinking that some of MS's ISO's are corrupt!! The latest MS 8.1 Pro ISO has so many issues with it its insane. Crikey.

Actually, scratch that I DO have something you can try. Try downloading the updates using WSUS offline update utility.

-Click the link, then go to the right of the page you will see blue text "Version 9.6" download it, unzip the file, run UpdateGenerator.exe , selecting the options/updates you want included, a CMD line will pop up. It is downloading the updates. It will let you know when it is done. Now, copy the "wsus96" folder to any of the offending computers, go into wsusoffline96\client, and run "UpdateInstaller.exe" selecting your desired options. Again a CMD line will pop up, it will install all the security updates plus IE 11 if you selected it (I would as its more secure) etc. Then your computer is secure for online use as far as that is concerned.

Hope this helps.