Just installed Ubuntu 10.10 netbook version on an older Dell Laptop (no other operating system installed). When hovering with mouse over menu bar, the full screen changes to default coloured back ground shortly and then back to normal (as after start-up) again. And that each time the mouse is over any of the (default) icons on the menu bar. I am not able to select any icon. No left or right click works on icons or anywhere on the menubar apart from the left top small icon, white Ubuntu logo, and the right top small icons for WiFi, sound, mail, shut-down etc. Those icons work. I tried re-installation again and all patches are downloaded. Same problem. Problem is that I can't enter commands either to reduce e.g. the swappiness (if that would be of any help). Can somebody help me that encountered similar problem or knows a resolution?