How to detect a key logger on my system

First I'd like to thank all of you for helping me through my hacker issues.

Second, I'd like to know if there is a way to detect a key logger on my system?

I was tempted to download one of the many programs online that does it. However, it asked that I close my anti virus program before installing it. Very reluctant to do that for a program I do not trust 100%.

Are there any programs online that I can trust? Or can I detect the key logger without using one of them?

I am running WinXP Home with all the updates. Subscribe to Liveonecare and it keeps everything current.

Thanks.

tbuccino--It is difficult to detect a Keylogger. This may be one of best ways to detect
http://technet.microsoft.com/en-us/s.../bb896645.aspx

These programs are reliable and may help remove
www.malwarebytes.org/mbam.php
http://www.superantispyware.com
http://www.download.com/Trend-Micro-...-10227353.html
http://www.emsisoft.com/en/software/free/
If you need help in interpreting the results from any of these, post in the HiJackThis forum here. Restate your question there so they know what you are looking for.
Here is a general reference that may help your understanding
http://www.tech-faq.com/remove-keylogger.shtml
Note the reference to using the onscreen keyboard.