Found this great video showing how to get into the advanced mode on the Aspire One.

Please remember these words of warning, however, as the description to the video states:

Walkthrough of how to activate the “advanced mode” in the Linpus OS on the Acer Aspire One. Proceed at your own risk, it is easy to mess up settings if you play around with them a lot!

Thanks to denial for posting the link (and for all the other tips).