vlc player takes over my computer

Hi when i install vlc player it takes over everything on my computer so if i click on itunes it brings up vlc player and when i restart my computer every icon changes to vlc player . the only way to stop is uninstall , i cant figure out whats causing all this any help on solving this problem cause vlc player is the only thing that works n gives me clear picture n sound on my tv . thank in advance

ive downloaded it from bothe filehippo/cnet/official site both 32/64 bit n bluray
OS Version: Microsoft Windows 7 Home Premium, Service Pack 3, 64 bit
Processor: Intel(R) Core(TM) i5-3330 CPU @ 3.00GHz, Intel64 Family 6 Model 58 Stepping 9
Processor Count: 4
RAM: 8156 Mb
Graphics Card: NVIDIA GeForce 210, 1024 Mb
Hard Drives: C: Total - 1907626 MB, Free - 1202964 MB;
Motherboard: Gigabyte Tecohnology Co., Ltd., H61MA-D2V
Antivirus: avast! Antivirus, Updated and Enabled