When I tried disenchanting at Dragonsreach lab I am limited to certain items like weapons, rings or boots, I don't seem to be able to choose any enchanted robes to disenchant.

When I use a public alchemy table I only get one item show on my list that doesn't do anything (charred skeever or something). In my Breezehome lab it shows all my ingredients.

Are these glitches with this character? I don't have my own enchanting table with this character yet to know if this is only with public enchanting tables like with the alchemy.

it does seem to be a glitch, I've never had that problem with dragonsreach's tables.

I got rid of the charred Skeever hide and my alchemy menu went normal, sold the robes and will wait till I get more later and retry.

If you already know an enchanting "effect", you can't keep learning the same enchantment from the table.

I have been able to disenchant the robes, but amulets and etc., aren't an option.

After I sold the cheaper robes I couldn't disenchant I went back with a very expensive robe and have the option but passed on doing so.