clickable_rows
<apex:page controller="one" action="{!save}">
<apex:form >
<apex:pageBlock id="one">
<apex:pageBlockTable value="{!accs}" var="a">
<apex:column value="{!a.id}"/>
<apex:column value="{!a.name}"/>
<apex:column >
<apex:commandButton value="click" action="{!save}" reRender="two">
<apex:param name="accountId" value="{!a.id}" assignTo="{!accid}"/>
</apex:commandButton>
</apex:column>
</apex:pageBlockTable>
</apex:pageBlock>
<apex:pageBlock id="two">
<apex:pageBlockSection >
<apex:pageBlockSectionItem >
ID:{!accid}
</apex:pageBlockSectionItem>
</apex:pageBlockSection>
</apex:pageBlock>
</apex:form>
</apex:page>