Implement multiple product chooser widget Magento

Question

Hi I need to implement a multiple product chooser widget in magento. For this I am using the below code. With this a I can put a multiple sku for the products in the field in admin. But I need to implement a product chooser with a checkboxes so that I can check those and submit. Please check the screenshot here http://www.awesomescreenshot.com/0035hy791a

app/code/community/Speroteck/SelectedProductsBlock/etc/config.xml

<config>
    <modules>
        <Speroteck_SelectedProductsBlock>
            <version>0.1.0</version>
        </Speroteck_SelectedProductsBlock>
    </modules>
    <global>
        <helpers>
            <speroteck_selectedproductsblock>
                <class>Speroteck_SelectedProductsBlock_Helper</class>
            </speroteck_selectedproductsblock>
        </helpers>
        <blocks>
            <speroteck_selectedproductsblock>
                <class>Speroteck_SelectedProductsBlock_Block</class>
            </speroteck_selectedproductsblock>
        </blocks>
    </global>
    <frontend>
        <layout>
            <updates>
                <speroteck_selectedproductsblock>
                    <file>speroteck/selectedproductsblock.xml</file>
                </speroteck_selectedproductsblock>
            </updates>
        </layout>
    </frontend>
</config>

app/code/community/Speroteck/SelectedProductsBlock/etc/widget.xml

<?xml version="1.0"?>
<widgets>
    <Speroteck_SelectedProductsBlock type="speroteck_selectedproductsblock/list" module="speroteck_selectedproductsblock">
        <name>Display selected products</name>
        <description>Display list of selected products</description>
        <parameters>
            <block_name translate="label">
                <label>Block Name</label>
                <type>text</type>
                <required>1</required>
                <visible >1</visible>
            </block_name>
            <template translate="label">
                <label>Frontend Template</label>
                <visible>1</visible>
                <required>1</required>
                <type>select</type>
                    <values>
                        <grid translate="label">
                            <value>speroteck/selectedproductsblock/default.phtml</value>
                            <label>Default template</label>
                        </grid>
                    </values>
            </template>
            <products_limit translate="label">
                <label>Products Limit</label>
                <type>text</type>
                <required>1</required>
                <visible >1</visible>
                <value>4</value>
            </products_limit>
            <selected_products>
                <label>Product sku's</label>
                <description>Product sku's separated by comma</description>
                <type>textarea</type>
                <required>1</required>
                <visible >1</visible>
            </selected_products>
        </parameters>
    </Speroteck_SelectedProductsBlock>
</widgets>

app/code/community/Speroteck/SelectedProductsBlock/Helper/Data.php

<?php
class Speroteck_SelectedProductsBlock_Helper_Data extends Mage_Core_Helper_Abstract
{
}

Please suggest me how can I implement a multiple product chooser in my plugin.

Thanks