I would suggest you to try the following methods and check if it works for you.
Try the steps provided in the following Microsoft Support article to troubleshoot script errors in Internet Explorer and check if it helps.
How to troubleshoot script errors in Internet Explorer:http://support.microsoft.com/kb/308260/en-us?wa=wsignin1.0
Try the steps provided in the following Microsoft Help article and check.
Is Internet Explorer slow? 5 things to try:http://windows.microsoft.com/en-us/windo...ost-performance
Disclaimer: The Reset Internet Explorer Settings feature might reset security settings or privacy settings that you added to the list of Trusted Sites. The Reset Internet Explorer Settings feature might also reset parental control settings. We recommend that you note these sites before you use the Reset Internet Explorer Settings feature.