我电脑有好几个月了一直没搞好，求大家帮帮忙呀，谢谢了
现象是：开机到桌面后偶尔自动闪黑屏，特别是启动程序时闪黑屏。
以下是扫描日志：
[CODE]
2010-05-25,23:32:00
System Repair Engineer 2.8.2.1321
Smallfrogs (
http://www.KZTechs.com)
Windows XP Professional Service Pack 2 (Build 2600) - 管理权限用户 - 完整功能
以下内容被选中：
所有的启动项目（包括注册表、启动文件夹、服务等）
浏览器加载项
正在运行的进程（包括进程模块信息）
文件关联
Winsock 提供者
Autorun.inf
HOSTS 文件
进程特权扫描
计划任务
Windows 安全更新检查
API HOOK
隐藏进程
启动项目
注册表
[HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run]
<ctfmon.exe><C:\WINDOWS\system32\ctfmon.exe> [(Verified)Microsoft Windows Publisher]
[HKEY_CURRENT_USER\Software\Microsoft\Windows NT\CurrentVersion\Windows]
<load><> [N/A]
[HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\CurrentVersion\Run]
<SoundMan><SOUNDMAN.EXE> [(Verified)Microsoft Windows Hardware Compatibility Publisher]
[HKEY_LOCAL_MACHINE\Software\Microsoft\Windows NT\CurrentVersion\Winlogon]
<shell><Explorer.exe> [(Verified)Microsoft Windows Publisher]
<Userinit><C:\WINDOWS\system32\userinit.exe,> [(Verified)Microsoft Windows Publisher]
[HKEY_LOCAL_MACHINE\Software\Microsoft\Windows NT\CurrentVersion\Windows]
<AppInit_DLLs><> [N/A]
[HKEY_LOCAL_MACHINE\Software\Microsoft\Windows NT\CurrentVersion\Winlogon]
<UIHost><logonui.exe> [(Verified)Microsoft Windows Publisher]
==================================
启动文件夹
N/A
==================================
服务
[Help and Support / helpsvc][Stopped/Disabled]
<C:\WINDOWS\System32\svchost.exe -k netsvcs-->%WINDIR%\PCHealth\HelpCtr\Binaries\pchsvc.dll><N/A>
[NetMeeting Remote Desktop Sharing / mnmsrvc][Stopped/Disabled]
<C:\WINDOWS\system32\mnmsrvc.exe><(File is missing)>
==================================
驱动程序
[Intel(r) 82801 Audio Driver Install Service (WDM) / ac97intc][Stopped/Manual Start]
<system32\drivers\ac97intc.sys><Intel Corporation>
[Service for Realtek AC97 Audio (WDM) / ALCXWDM][Running/Manual Start]
<system32\drivers\ALCXWDM.SYS><Realtek Semiconductor Corp.>
[Creative SBLive! Gameport / ctljystk][Stopped/Manual Start]
<system32\DRIVERS\ctljystk.sys><Creative Technology Ltd.>
[nv / nv][Running/Manual Start]
<system32\DRIVERS\nv4_mini.sys><NVIDIA Corporation>
[Direct Parallel Link Driver / Ptilink][Running/Manual Start]
<system32\DRIVERS\ptilink.sys><Parallel Technologies, Inc.>
[Realtek RTL8139(A/B/C)-based PCI Fast Ethernet Adapter NT Driver / rtl8139][Running/Manual Start]
<system32\DRIVERS\RTL8139.SYS><Realtek Semiconductor Corporation>
[Secdrv / Secdrv][Stopped/Manual Start]
<system32\DRIVERS\secdrv.sys><N/A>
[SIS AGP Bus Filter / sisagp][Running/Boot Start]
<\SystemRoot\system32\DRIVERS\sisagp.sys><Silicon Integrated Systems Corporation>
[SiS PCI Fast Ethernet Adapter Driver / SISNIC][Stopped/Manual Start]
<system32\DRIVERS\sisnic.sys><SiS Corporation>
[TCP/IP Protocol Driver / Tcpip][Running/System Start]
<system32\DRIVERS\tcpip.sys><Microsoft Corporation>
[VIMICRO USB PC Camera / ZSMC302][Running/Manual Start]
<System32\Drivers\usbVM31b.sys><VM>
==================================
浏览器加载项
[ThunderAtOnce Class]
{01443AEC-0FD1-40fd-9C87-E93D1494C233} <C:\Program Files\Thunder Network\Thunder\ComDlls\TDAtOnce_Now.dll, Thunder Networking Technologies,LTD>
[Thunder Browser Helper]
{889D2FEB-5411-4565-8998-1DD2C5261283} <C:\Program Files\Thunder Network\Thunder\ComDlls\xunleiBHO_Now.dll, (Signed) Thunder Networking Technologies,LTD>
[]
{E0E899AB-F487-11D5-8D29-0050BA6940E3} <, >
[ThunderAtOnce Class]
{01443AEC-0FD1-40FD-9C87-E93D1494C233} <C:\Program Files\Thunder Network\Thunder\ComDlls\TDAtOnce_Now.dll, Thunder Networking Technologies,LTD>
[Thunder Browser Helper]
{889D2FEB-5411-4565-8998-1DD2C5261283} <C:\Program Files\Thunder Network\Thunder\ComDlls\xunleiBHO_Now.dll, (Signed) Thunder Networking Technologies,LTD>
[使用迅雷下载]
<C:\Program Files\Thunder Network\Thunder\Program\GetUrl.htm, N/A>
[使用迅雷下载全部链接]
<C:\Program Files\Thunder Network\Thunder\Program\GetAllUrl.htm, N/A>
[导出到 Microsoft Office Excel(&X)]
<res://C:\PROGRA~1\MICROS~2\OFFICE11\EXCEL.EXE/3000, N/A>
[添加到QQ表情]
<C:\Program Files\Tencent\QQ\AddEmotion.htm, N/A>
==================================
用户系统信息：Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1; SV1)