You can set background image using style property of table, and also for cell. see below markup
<table cellpadding="5" cellspacing="5" class="style1"
style="background-image: url('table_bg.jpg')">
<tr>
<td style="background-image: url('cell1_jpg.jpg')">
1</td>
<td style="background-image: url('cell2_jpg.jpg')">
2</td>
</tr>
<tr>
<td style="background-image: url('cell3_jpg.jpg')">
3</td>
<td style="background-image: url('cell4_jpg.jpg')">
4</td>
</tr>
</table>