Excellent post by Zaikesman, as usual. That about covers it, I think. All four of the earlier VU studio albums have their own distinctive sound, and all are essential, including 'Loaded'. My personal favorite is the third album, quieter and more lyrical than anything else they ever did. And it has 'Pale Blue Eyes', one of rock's most beautiful songs.
As for Reed's solo career, I take exception to the post above that described it as consisting mostly of crap. Assuredly, there are weak spots, but some of the better Reed albums--especially 'Blue Mask'--are as good, if not as seminal, as the VU albums. Even his last one, 'Ecstasy', is a very good album.