Help me with my dell inspiron 1545 please !!

hello, I have a dell inspiron 1545 3GB ram , 160GB hard , 32bit operation system
I had windows vista home premium installed in ma system but i didnt like it so i installed windows 7 32bit in my system , it works fine but most of my laptop's fuctions wont work on it , Like when i turn down my laptop's volume it doesnt show me in the display but it works , same with the brightness and Wlan switch button, they all work perfactly fine but without any screen display , it used to come with the display on windows vista and i had a webcam studio installed in ma laptop with windows vista that allowed me to take pictures and record videos through ma webcam and save them on my pc ,Does windows 7 has any webcam software like this ? one more thing ,My webcam wont work with my msn live messanger, I works fine with yahoo messanger or on facebook an youtube ,when i try it on my msn it says'' messanger's not ready for webcam try again later' i tried everything uninstalling webcam driver and msn messanger but nothing worked, PLEASE help me , anything would work ! thanks !

Drivers & Downloads=

I'm not sure that you'll find all that you want there, but it's a start.

You may find more under Vista.

I have tried all of em , didnt help , can we use vista's drivers on windows 7 ?