:-[ :-[ :-[ hi last evening my computer got infected with a spyware .
whenever i try to open a folder firefox opens automatically and opens an antivirus scanner page i know it's a spyware and just few seconds ago removed it with superantispyware.
but i want a free spyware which provides real time protection.
please suggest which antispyware to use also if possible please give their ram usage on vista.

You may try Spyware Doctor but best practice is to do intelligent browsing.
If you remember, Comodo firewall also comes with antispyware / virus scanner... though its basic.

You may download Spyware doctor free with google pack.

I suggest you to install comodo firewall and keep track of every activity on your computer.

Also, most of the latest antivirus softwares are capable enough to detect and remove spyware too.