Black Screen

Sometimes when I run some programs or flash games my monitor will become black and unresponsive. Sometimes it only flashes black when move the mouse. I am not very good with computers what can I try to fix it? Here is my computers info. Wasn't sure what was all important. Sorry if I posted too much or too little.

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System Information
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Time of this report: 12/10/2012, 19:38:08
Machine name: N-1VP0QXQG9958Z
Operating System: Windows XP Home Edition (5.1, Build 2600) Service Pack 3 (2600.xpsp_sp3_gdr.120821-1629)
Language: English (Regional Setting: English)
System Manufacturer: AWARD_
System Model: AWRDACPI
BIOS: Phoenix - AwardBIOS v6.00PG
Processor: Intel(R) Pentium(R) 4 CPU 3.00GHz (2 CPUs)
Memory: 1024MB RAM
Page File: 496MB used, 1197MB available
Windows Dir: C:\WINDOWS
DirectX Version: DirectX 9.0c (4.09.0000.0904)
DX Setup Parameters: Not found
DxDiag Version: 5.03.2600.5512 32bit Unicode

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Display Devices
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Card name: NVIDIA GeForce FX 5500
Manufacturer: NVIDIA
Chip type: GeForce FX 5500
DAC type: Integrated RAMDAC
Device Key: Enum\PCI\VEN_10DE&DEV_0326&SUBSYS_00000000&REV_A1
Display Memory: 256.0 MB
Current Mode: 1440 x 900 (32 bit) (60Hz)
Monitor: Plug and Play Monitor
Monitor Max Res: 1600,1200
Driver Name: nv4_disp.dll
Driver Version: 6.14.0011.7519 (English)
DDI Version: 9 (or higher)
Driver Attributes: Final Retail
Driver Date/Size: 5/16/2008 14:01:00, 6108928 bytes
WHQL Logo'd: Yes
WHQL Date Stamp: n/a
VDD: n/a
Mini VDD: nv4_mini.sys
Mini VDD Date: 5/16/2008 14:01:00, 6557408 bytes
Device Identifier: {D7B71E3E-4066-11CF-EF7E-0B2000C2CB35}
Vendor ID: 0x10DE
Device ID: 0x0326