I found a work-around:
I used the nomodeset option in the grub bootloader. There are two methods to
set nomedest:
Temporal: while booting press and hold shift in order to see the grub menu.
Choose the entry you want to change (in a normal installation the first entry)
and press e to edit it.
The same problem persists with the most recent version of Skype
(skype_4.3.0.37) and Xubuntu 14.04 updated until today (September 6th 2014).
It affects Dell Computers (Dell Optiplex 170L) with an Intel 82865G integrated
Graphics Controller and Xubuntu 14.04 32-bit.
Several different Webcams
