Warning, if your not familiar with Microsoft operating sytems, this utility may be difficult to use.
Download and run Autoruns from below site (look to top right of page, section "Top 10 Downloads")
After Autoruns lists your systems startup programs, Check the following menu options:
Menu->Options->Verify code signatures->Checked
Menu->Options->Verify code signatures->Hide Signed Microsoft Entries->Checked
Menu->File->Refresh
Look at the publisher field, anything with status (Not Verified) and from a company you aren't familiar with requires further investigation. Below site can be used to query particular files.