Hm.. I'm a Mage Guild member in the Dark Brotherhood! A not so pleasant combination.
By the way, AA and HDR don't work together. Neither do AA and Bloom, but they don't tell you that. Try disabling AA with bloom and you'll be able to see the sun, but some things will appear more jaggedy (like the water). I really don't want to disable bloom but I don't like the jagged look. Oh well.
Btw, check this out
Press ~
then type setfog 1000 80000
well mess around with the numbers for a bit. Try and fog the game up if your GFX card is old and maybe that'll help, or you can follow an ini tweak guide to see what'll work.