A Flash drive is a memory stick. I doubt you need that to watch Flash videos or play Flash games.
I'm guessing you need a Flash Plugin for your internet browser. I would visit http://get.adobe.com/flashplayer/otherversions/ with your browser and search for the right plugin there.
Alternatively have a look at http://www.ubuntuupdates.org/package/core/oneiric/multiverse/base/flashplugin-downloader
As to installing Windows, without a genuine Windows CD (XP) or DVD, (Vista or Win 7), you won't be able to do that, but if this Dell had a hidden recovery partition, (accessible via the BIOS POST messages when you turn the system on), and if this hidden partition wasn't wiped when this friend of a friend erased Windows, then you can use that to return the system to factory state.
Why not ask the first friend for the Windows disk?
Mark
it had a password on it so they took it to another friend that erased windows vista and it now has ubuntu 11.10 i need to know if there is any way of putting windows back on i have no disk if no then how do i install a flash drive in ubuntu? ive gone to the ubuntu software center and tried to download adobe but it says the file no longer exsist i cant get onto facebook and watch videos or plat games
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