I lost my sound i dont know what to do!

[xanithis]

i know very Little about computers so I'm going to just tell you everything i know

the facts
the set up: i have never changed the sound card i used the one that came with the computer a dell dimension 9100. i have never unplugged the speakers. i bought some head phones and occasionally plugged those in

what happened: i had plugged in the head phones and everything was working fine then when i unplugged my headphones my sound had disappeared. I'm guessing that it might have something to do with the fact that i have to safely remove hardware but i don't know

the symptoms: now the sound is gone but my speakers are still emitting something when i cranked the volume up to max i found that it would emit some staticy feedback (I'm not sure if that's the technical term but that's what Ive come to call it)  this static plays whenever sound should be playing or when things in the window move (for example if i min or max a window or if i scroll around the screen.) 
also when i plugged in my headphones after the problem the same static came from the head phones.

its not the first time: this happened to me last year but the issue (as far as i know) magically resolved itself. i was playing left 4 dead and had left the menu sitting there for a while and when i move the mouse over the buttons the buttons made a "click" noise. i don't know why it happend

what i think it isn't
i had gone through most of windows trouble shooter and found out the following

my volume is proprely adjusted

there are no hardware conflicts (since I'm not familiar with any of the terms that appeared under the audio device list it is a possibility that it might be the issue but i didn't see any exclamations or X's so I'm guessing that's not the problem)

everything is plugged in.

when the trouble shooter recommended changing the BIOS i decided that i was not an advanced enough user and i didn't want to risk further screwing my computer.

so what i need to know is this
how can i restore my sound back to normal.

[GlitchPC]

Do you plug your headphones into a speaker or the computer itself?

Never, ever, plug something into something else if the computer and/or speakers are on...unless you're plugging in a USB cable...and that, too, can create ESD (Electrostatic discharge), which is what I think happened in this case.

You probably damaged your sound card.

If you have another sound card available...test it on this computer.  Otherwise...you're just grasping at straws...since this does not appear to be a driver-related issue.  Just a simple case of ESD.