I upgraded to 12.04.1 from 10.04 recently and am running the Gnome Classic (no effects) desktop. I spent a couple of days tweaking the appearance and behaviour but there are two issues that I can't resolve.
The mouse cursor frequently disappears, especially when scrolling through web pages or hovering over links/icons with tooltips. Moving the mouse brings the pointer back but it vanishes again almost immediately. Note I don't have unclutter or Parallels installed.
The screen no longer fades to black when left idle for too long - it just cuts out. Bad news when watching content online.
EDIT: It's a 2 year-old Acer Aspire One laptop with 2x Intel Atom Z520 processors @ 1.33GHz, 1GB RAM, Intel GMA500 Poulsbo graphics card. I originally installed 10.04 via Wubi and upgraded to 12.04 via Update Manager.
Any tips greatly appreciated. Cheers...