Vista - TASKBAR NOT WORKING PROPERLY!!!

I have windows vista 32 bit w/1.3gb RAM & AMD Sempron 1.5 ghz

PLEASE HELP ME!!! When I click on the start button, it works but, when I
minimise any window or program and I go to click on anything on the taskbar,
I get that annoying "ding" sound. I have to open the task manager to close
the open windows or programs because I can't maximize them because when I
click on them I hear that "DING" sound. The items by the clock still work, I
can see animations and stuff(network notification, myspace messages etc.)
but, nothing shows up when I roll the mouse over the buttons or when I try to
click on the volume icon once again I get that annoying "DING" sound. I
tried restarting but, to no evail so , if anyone can help me, PLEASE!!! do so
I will be forever in your debt(that's a figure of speach of course.)