Spyware Scanner and Keylogger

[Transcendent Clarity]

So yesterday my spyware scanner does a automatic scan and found a keylogger. I blocked it and deleted it, from guildwars, keyloggers are undetectable from spyware scanner and virus scanners. But I've found 1 and removed it, I'm being very cautious because I found it early I haven't played guild wars and haven't logged to anything that required a password.
I spent the entire day scanning my computer for others. So far, my computer is clean, but that could just mean that its undetectable. I even went and ask a friend of mine to see if I was online in guild wars during the time I was scanning, I wasn't. Now I'm being cautious and need an advice if I should log into anything and be a risk of getting my account stolen. I found the keylogger before logging into anything, so if I should change my password it would risk of getting my account stolen because hidden keyloggers are there and they haven't know my present password so changing it would risk it. Now I don't know what to do, should I risk it? Having scanned my computer previously and it was clean, could mean that I have hidden keyloggers.

[Mr Panda]

If your account has remember email address ticked, you can add

-password yourpasswordhere

To the shortcut, this means, when you run the shortcut, guildwars will login, with that password. This has pros and cons;

Pro: You dont type the password so a keylogger cant pick it up
Con: The password is stored in an unencrypted file, probably on your desktop.

Thats the only real solution to prevent keylogging stealing your account, but its not without its own flaw.

Other than that, for total peace of mind, only thing I can think of is a format + reinstall, which will result in a 'clean' pc.

[Transcendent Clarity]

Should I make a new e-mail address and other things requiring a password to see if its being used or not? Reformatting my computer is my last resort so I want to make sure before doing it. The Dragon Festival is almost over and want to get this over with T.T