In addition to the fine recommendations already given, use Firefox as your default browser. Although IE7 is far more secure than IE6 was, Firefox keeps you even safer from hidden threats.

Some other tips, regardless of your browser choice:
  • Always use the popup blocking feature.
  • Never click OK or Yes to a dialog box that pops up while browsing unless you have explicitly clicked on something to cause the dialog box to appear, or you are trying to download something.
  • Don't open email attachments unless you are expecting them -- even if it is from someone you know. Double-check with the source if you're unsure.