App Crash Problem In WIN 7

Hello everybody ! I face App crash problem in my system. When i install avast antivirus or any other application i got this problem. I am posting contents of problem which is :-


Problem signature:
Problem Event Name: APPCRASH
Application Name: avast_free_antivirus_setup_2014.9.0.2007.exe
Application Version: 9.0.2013.292
Application Timestamp: 52dea99e
Fault Module Name: avast_free_antivirus_setup_2014.9.0.2007.exe
Fault Module Version: 9.0.2013.292
Fault Module Timestamp: 52dea99e
Exception Code: 80000003
Exception Offset: 05668087
OS Version: 6.1.7600.2.0.0.256.1
Locale ID: 1033
Additional Information 1: 626f
Additional Information 2: 626f9d8190473f6468992d3725957367
Additional Information 3: d29b
Additional Information 4: d29b16f90c0c14edb89666c3cf79189f

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Windows 7 Privacy Statement - Microsoft Windows

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C:\Windows\system32\en-US\erofflps.txt


For resolving this i reinstall the win 7 (formatting only the root drive c:) but problem remain.
and also select the "turn on DEP (Data execution prevention) for all program and services except those i select , option Avail under the system maintenance tab (view under the computer properties) but following error coming when add any program:- "this program must run with DEP enabled. you cannot turn off DEP for this program. But above setting does not work.
Please help me
system specification:-
OS - Windows 7 ultimate edition 32 bit
Processor : Intel core 2 CPU 630 1.86 GHZ with 2 GB RAM

@Ztruker
This problem not with Avast antivirus , happen with every application like VLC media player , IDM and many more application. Now What should i do .