Since I have procured my laptop I have been using Ubuntu Fiesty Fawn (7.04) on it and I was more than satisfied until its support period expired on Jan 2009; I was compelled to upgrade and I did not want to take the hassle of upgrading again in the lifetime of this laptop so I decided to upgrade to Hardy Heron (8.04 LTS) (via Gutsy Gibbon). This writeup is my experience on this upgrade procedure.
My laptop is a Acer 5585WXMi, with GeForce Go 7300 VGA card, 802.11a/b/g WLAN, 5-in-1 Card Reader and Bluetooth built-in. In Fiesty all devices were recognized perfectly other than the Card Reader, did not spent much time on it since it was not much used by me.
The first hitch I faced was I found that Fiesty repository aren't there anymore so I disabled them from APT source list (/etc/apt/source.list or package manager). Then I started upgrading to Gutsy. During package installation it was trying to modify some configurations that I had earlier edited for my usage and also some which I had never touched :), so I looked at the difference (both upgrade from console and UI has it - 'd' from console) and took appropriate action. Most cases I let it override, the exception was MySQL and some other packages. The first problem I faced after upgrading to Gutsy was the display as it was stuck with 640x480 resolution and it was quite frustrating, but before spending more time on it I moved on to upgrading to Hardy.
During upgrading to Hardy all went smooth except for Slapd upgradation failed because the slapd database had data from unconfigured domain which was okey @ Fiesty and Gutsy. So after installation I manually restored the data from the backedup LDIF file and Slapd configuration was successful. But VGA was a pain as usual :(. Cutting the long story short to get the VGA to work all I had to do was enable the restricted NVidia driver and delete the /etc/X11/xorg.conf (obviously after backing up), followed by OS reboot and guess what now I can enjoy 1280x800 resolution :). Now a side note - I got the 'vesa' driver to work with 1024x768 but the problem was everything was vertically squeezed and it was depressing especially to view the photographs I took myself. Plus I also ran into problem using MSN & GTalk with Pidgin because of SSL lib issue (I am not certain why, but it could be related to my attempt to install pidgin on fiesty from source without SSL). So I uninstalled pidgin related packages and installed it from source by the help of this post; please add '--with-system-ssl-certs=/etc/ssl/certs' option during build else you will face unwanted hazards with certificate chain. Another problem faced was the Flash plugin of Firefox was not producing sound. For that I simply set all devices @ System -> Preferences -> Sound to use ALSA (by default it is PulseAudio). Plus I needed support for 'docx' and for that I needed OpenOffice 3. So I uninstalled all OpenOffice packages from my installation and downloaded DEB packages from OpenOffice.org and installed them using 'dpkg'. After main DEBs are installed check the DEB folder for another DEB @ 'desktop-integration/', that will create the menu shortcuts for you.
For photographers and users interested in graphics package you will find 'ubuntustudio-graphics' package useful, one might also find other ubuntustudio packages (apt-cache search ubuntustudio) useful - it has audio, video, desktop etc. packages for enthusiasts and professionals.
In a nutshell, now my Hardy is totally under control and I am enjoying using it :), so if anyone has not upgraded to Hardy yet please do so :).