Multiple Category Issue

Hi all,

Ive just started using wordpress and have been messing about all of today. I have had a search on the forums but not found anything that answers my question fully.

Basically in the sidebar I would like 2 seperate category sections so:

Articles
-article 1
-article 2

Topic of the Week
-topic a
-topic b

I would prefer this than having then under the same category heading like this :-

Categories
-Articles
–article 1
–article 2
-Topic of the Week
–topic a
–tobic b

I dont want all the posts to show when the “articles” or “topic of the week” heading is clicked so making them two seperate categories would stop this. I dont want those to be clickable at all, only the subcats. Is this possible?

I hope this is clear! If not im really sorry and please ask questions so I can help explain myself better!

I really appreciate any help!

Thanks,