the computer screen crashes (crash) and makes strange lines and I have to turn off, I can not do anything

the computer screen crashes (crash) and makes strange lines and I have to turn off, I can not do anything

ProblemType: Bug
DistroRelease: Ubuntu 12.04
Package: xorg 1:7.6+12ubuntu1
ProcVersionSignature: Ubuntu 3.2.0-31.50-generic 3.2.28
Uname: Linux 3.2.0-31-generic x86_64
NonfreeKernelModules: nvidia
.proc.driver.nvidia.gpus.0: Error: [Errno 21] È una directory: '/proc/driver/nvidia/gpus/0'
.proc.driver.nvidia.registry: Binary: ""
.proc.driver.nvidia.version:
 NVRM version: NVIDIA UNIX x86_64 Kernel Module 295.40 Thu Apr 5 21:37:00 PDT 2012
 GCC version: gcc version 4.6.3 (Ubuntu/Linaro 4.6.3-1ubuntu5)
.tmp.unity.support.test.0:

ApportVersion: 2.0.1-0ubuntu13
Architecture: amd64
CompizPlugins: [core,bailer,detection,composite,opengl,decor,vpswitch,move,grid,compiztoolbox,mousepoll,place,wall,imgpng,unitymtgrabhandles,gnomecompat,resize,snap,regex,session,animation,workarounds,expo,ezoom,fade,scale,unityshell,dbus]
CompositorRunning: compiz
Date: Thu Sep 13 02:11:06 2012
DistUpgraded: Fresh install
DistroCodename: precise
DistroVariant: ubuntu
ExtraDebuggingInterest: Yes, if not too technical
GraphicsCard:
 NVIDIA Corporation Device [10de:0df1] (rev a1) (prog-if 00 [VGA controller])
   Subsystem: Acer Incorporated [ALI] Device [1025:035a]
InstallationMedia: Ubuntu 11.10 "Oneiric Ocelot" - Release amd64 (20111012)
JockeyStatus:
 xorg:nvidia_current - NVIDIA accelerated graphics driver (Proprietary, Enabled, In use)
 xorg:nvidia_current_updates - NVIDIA accelerated graphics driver (post-release updates) (Proprietary, Disabled, Not in use)
MachineType: Acer Aspire 5745G
ProcEnviron:
 PATH=(custom, no user)
 LANG=it_IT.UTF-8
 SHELL=/bin/bash
ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-3.2.0-31-generic root=UUID=f1721e72-0581-4dc1-bc78-5e2c5f038ae8 ro quiet splash vt.handoff=7
SourcePackage: xorg
UpgradeStatus: No upgrade log present (probably fresh install)
XorgConf:
 Section "Device"
  Identifier "Default Device"
  Option "NoLogo" "True"
 EndSection
dmi.bios.date: 22/03/2011
dmi.bios.vendor: INSYDE
dmi.bios.version: V1.19
dmi.board.asset.tag: Base Board Asset Tag
dmi.board.name: JV53_CP
dmi.board.vendor: Acer
dmi.board.version: Base Board Version
dmi.chassis.type: 10
dmi.chassis.vendor: Chassis Manufacturer
dmi.chassis.version: Chassis Version
dmi.modalias: dmi:bvnINSYDE:bvrV1.19:bd22/03/2011:svnAcer:pnAspire5745G:pvrV1.19:rvnAcer:rnJV53_CP:rvrBaseBoardVersion:cvnChassisManufacturer:ct10:cvrChassisVersion:
dmi.product.name: Aspire 5745G
dmi.product.version: V1.19
dmi.sys.vendor: Acer
version.compiz: compiz 1:0.9.7.8-0ubuntu1.4
version.ia32-libs: ia32-libs 20090808ubuntu36
version.libdrm2: libdrm2 2.4.32-1ubuntu1
version.libgl1-mesa-dri: libgl1-mesa-dri 8.0.4-0ubuntu0.1
version.libgl1-mesa-dri-experimental: libgl1-mesa-dri-experimental N/A
version.libgl1-mesa-glx: libgl1-mesa-glx 8.0.4-0ubuntu0.1
version.nvidia-graphics-drivers: nvidia-graphics-drivers N/A
version.xserver-xorg-core: xserver-xorg-core 2:1.11.4-0ubuntu10.8
version.xserver-xorg-input-evdev: xserver-xorg-input-evdev 1:2.7.0-0ubuntu1.2
version.xserver-xorg-video-ati: xserver-xorg-video-ati 1:6.14.99~git20111219.aacbd629-0ubuntu2
version.xserver-xorg-video-intel: xserver-xorg-video-intel 2:2.17.0-1ubuntu4.1
version.xserver-xorg-video-nouveau: xserver-xorg-video-nouveau 1:0.0.16+git20111201+b5534a1-1build2