Hey, it sounds like u need to update your machine as well, goto
www.windowsupdate.com and make sure you have as many as the updates as possible, it's up to you whether or not you choose to go to windows xp service pack 2, i take it windows xp is your operating system, you'll know this as when you turn your machin on it'll say it.? Go to that site and try updating everything, i would recommend to begin with you don't get service pack 2, just click on the "review other updates" if prompted for service pack 2.
I think that should sort out most of your problems.
Id like to know who said it could be your motherboard, thats the main and most crucial piece of equpment of your machine, it's the big circuit board that everything is plugged in to.? Although they do go wrong, it doesn't sound like it has in your case, usually if it has gone wrong your wouldn't even be able to go in to windows. What you have sounds like windows and Internet explorer needs patching, something this updating will fix. If you do have all the above software installed it still won't prevent you from getting a few bugs if your machine is not up to date so give it ago!
anyways, try updating and let us know how u get on