Download Firefox, and download the tidy plugin. You can see where the HTML breaks at.
line 34 column 45 - Warning: <img> element not empty or not closed
line 35 column 43 - Warning: <img> element not empty or not closed
line 36 column 45 - Warning: <img> element not empty or not closed
line 82 column 1 - Warning: <hr> element not empty or not closed
line 94 column 1 - Warning: missing <li>
line 97 column 1 - Warning: <input> element not empty or not closed
line 98 column 1 - Warning: <input> element not empty or not closed
line 99 column 1 - Warning: <input> element not empty or not closed
line 105 column 1 - Warning: <hr> element not empty or not closed
line 141 column 5 - Warning: missing </small> before <div>
line 141 column 32 - Warning: inserting implicit <small>
line 141 column 82 - Warning: discarding unexpected </small>
line 169 column 5 - Warning: missing </small> before <div>
line 169 column 32 - Warning: inserting implicit <small>
line 169 column 84 - Warning: discarding unexpected </small>
line 194 column 5 - Warning: missing </small> before <div>
line 194 column 32 - Warning: inserting implicit <small>
line 194 column 83 - Warning: discarding unexpected </small>
line 221 column 5 - Warning: missing </small> before <div>
line 221 column 32 - Warning: inserting implicit <small>
line 221 column 83 - Warning: discarding unexpected </small>
line 98 column 1 - Warning: <input> proprietary attribute "border"
line 168 column 5 - Warning: <h2> anchor "post_title" already defined
line 169 column 12 - Warning: <div> anchor "post_date" already defined
line 193 column 5 - Warning: <h2> anchor "post_title" already defined
line 194 column 12 - Warning: <div> anchor "post_date" already defined
line 220 column 5 - Warning: <h2> anchor "post_title" already defined
line 221 column 12 - Warning: <div> anchor "post_date" already defined
line 141 column 5 - Warning: trimming empty <small>
line 169 column 5 - Warning: trimming empty <small>
line 194 column 5 - Warning: trimming empty <small>
line 221 column 5 - Warning: trimming empty <small>
0 errors / 32 warnings
0 errors / 32 warnings
That may or may not fix it, but once you fix those, you can see where else it needs to be fixed.