Can someone tell me how to make the password NOT require special characters?

Open your web.config and add the following changes to the membership section (in bold):

<membership defaultProvider="YafMembershipProvider" hashAlgorithmType="SHA1">
<providers>
<clear/>
<add connectionStringName="yafnet" applicationName="YetAnotherForum" minRequiredPasswordLength="5" minRequiredNonAlphanumericCharacters="0" name="YafMembershipProvider" requiresUniqueEmail="true" useSalt="true" type="YAF.Providers.Membership.YafMembershipProvider"/>
</providers>
</membership>