You can upgrade to Karmic from an existing install. Upgrade Ubuntu 9.04 (Jaunty Jackalope) to Ubuntu 9.10 (Karmic Koala) Beta|Ubuntu Geek
This should work, but it's always a good idea to back everything up.
Or if you have a separate /home folder, you can do a clean install, but leave /home unformatted, so all your personal settings and info remain untouched. In this case, you would have to reinstall any software or apps you installed before, like ubuntu-restricted-extras. Quote:
I think firefox came online quicker -
did not seem to hang for so long before finding google etc...
| This might be due to ipv6. In brief, ipv6= internet protocol version 6. The current standard is ipv4.
Basically what happens is, your computer asks for ipv6 addresses first. But most sites don't use ipv6 yet. The appropriate response is for your router to say, "What the hell are you talking about?" and move on to resolve an ipv4 address. But what happens in practice is that the router just ignores the request, and your computer sits idly by waiting for an answer until the request times out. Hence the delay.
You can disable ipv6 to prevent this. A lot of people don't like that solution, because it's not really the fault of ipv6, but how the router handles name resolution, but it works. Interphero Miscellany Disable IPv6 in Ubuntu |