So I have a Lenovo T410i laptop which I bought last May (2010).
It is mainly Windows 7 system but I installed ubuntu as a dual booting and it really worked fine...until starting few months ago, my Windows tends to get freeze for no reason. It works fine but the internet stopped every 30 minute (long loading for 10 second then comes back) and also my task bar freezes and so many annoying thing going on.
I do not know why...when I used anti-virus program, it didn't really detect any so I don't know if this is due to hardware failure or viruses....It happened every time and I do wondering if this is because of dual boot? My ubuntu works fine...but I think it has overheating problem...It gets really hot sometimes.
So anyway, I am trying to re-install Windows only given that I have dual boot system...Would it be possible to uninstall Windows 7 and re-install it?
Also, another quick question is that my desktop (with Windows 7), whenever I go to "Network Sharing Center" -> "Change adapter setting" and click right click for one of those to see properties, it also freezes...Can someone also tell me why? It does it all the time...
You say you have a dual boot setup so I am going to assume that you have Windows 7 and Ubuntu installed on seperate partitions.
I can at least answer part of your question. Yes you can reinstall Windows 7. Just boot from the Windows 7 disc, choose the partition that is your Windows install and go to town. If you prefer to start clean, you can format the Windows partition first, then install Windows. As long as you don't mess with the partitions where your Ubuntu install lives your install will be fine.
Now, that said, reinstalling Windows 7 will most likely replace your bootloader (grub I assume?). In order to get back to dual booting, you are going to have to boot from your Ubuntu disk and reinstall the bootloader. The nice folks at Ubuntu have a good walkthrough for this part: https://help.ubuntu.com/community/RecoveringUbuntuAfter...