script error on start-up/computer very slow - please help

I keep getting a script error when the laptop turns on that says somthing like - error running scripts on this page, line 30, char 3, file:///C:/Program%20Files%20(x86)/Dell%20Support%20Center/sscommon/common/inc/ss_shellinclude.js

I don't know how to make it go away.  In addition, when browsing on the internet, it has gotten so slow.  It takes a really long time for each page to load and seems to be getting worse. Its to the point where I use my iPhone to look things up.  I have run a malware program and I have Kaspersky.  I am not a computer expert and I don't know how to fix this problem.  Any help would be appreciated.