If I'm not mistaken, your Acer Aspire 9420 is around 8 years old, came with Windows Vista pre-installed, and has 1GB of memory or maybe 2GBs (spec sheet here
Frankly, at this point in its life, it's doubtful that it will run anything
terribly well, although it is possible you can squeeze some last bits of life out of it with an ultra-light Linux distro, such as CrunchBang. Suggestion: if you're about to do a Ph.D., its time for a new laptop.
You can try taking the steps below to reduce UberStudent's footprint and see how that works.
As you found, to fix the Dbus error, go to Settings menu > Administration > Session and Startup > Application Autostart and un
tick Menu Pre-Start. Done.
Chromium: try propagating the profile again. Hit F12 on your keyboard to open Guake terminal and run:
rm -r $HOME/.config/chromium
Or take that step manually: open your home directory in the file manager, hit Ctr+H on your keyboard to show hidden files, enter the .config folder, manually delete the chromium folder, and then try running Chromium again.
You can lighten the load on your Acer with UberStudent by again going to Settings menu > Administration > Session and Startup > Application Autostart and un
ticking the following, if they are ticked:
- Allows Ctrl+Alt+Backspace....
- Backup Monitor
- Desktop Compositing
- Startup Sound
- UberStudent Logo
- Upgrade Notifier
- Upload Tool
- Xfdashboard Daemon
- Zeitgeist Datahub
Also, if you don't use Bluetooth, un
tick Indicator Bluetooth.
You can lighten the load further by un
- Guake Terminal
That should help considerably without sacrificing too much functionality.