Today i installed kubuntu on top of Windows7 using Wubi, which creates a linux disc image in the NTFS partition where windows is installed...
The first problem i encountered after installing kubuntu was: "Try hd(0,0):NTFS5: No wubildr" after selecting kubuntu from the boot menu...
This is because Windows7 has an hidden System partition before the actual partition. The bootloader tries to locate the wubildr files, but can not find it at this partition and after some time looks on the second partition, where the wubildr files are copied by the installation.
This can be fixed easily by copying the 2 wubildr files to the Windows7 system partition.
Since it can not be seen under Windows, i have done it in kubuntu (just the two files wubildr and wubildr.mbr).
The partition can be seen in the kubuntu file manager.
Second problem was that the second screen was not working. I installed the Nvidia native drivers and had to adjust the "nvidia x-server settings". It can be accessed by "nvidia-config" as root user using the console.
The second monitor might still be disabled - change its mode to: TwinView. Adjust the settings and "save to X config file". This should keep the settings also after rebooting. If that does not work, run nvidia-xconfig first - as root.
Also a second grub boot menu was showing up, which i disabled in the config file "/etc/default/grub". Changed the setting to: GRUB_TIMEOUT="0"
To save the settings after restart, use: update-grub command as root.
I had very slow browsing in either Konqueror and Firefox and my research turned out that it was caused by IPV6 being enabled by default no ubuntu.
There are several ways to disable it, i used all and do not know which one worked for me:
Change files: blacklist or blacklist.conf
Add: blacklist ipv6
Add: alias net-pf-10 off ipv6
In Firefox enter the URL: about:config
The setting network.dns.disableIPv6 can be set to true, but this is a firefox - only setting...
(won't work for any other applications).