As Nancy said, use iframe. I find it simply, clean, and reliable. I used it here to embede a blog into a webpage: http://amandashieldsmusic.com/blog.html
The code for that was so simple:
<iframe src="http://theshields.tumblr.com" width="1000px" height="600px">
your browser seems to not like this iFrame. Upgrade to something not ancient!