Troubleshoot Vista Update

Hi.

Can some one please tell me how I can download and install missing Windows
Vista Updates.
My systems says it is up to date and that there are no updates available at
this time even though I have only about 10 or 11 uodates installed I was
interrupted while downloading DreamScene content and after that I can't get
to these downloads anymore.
I also think there are more than 11 Vista security updates.
I cleaned the cache and cookies but this didn't help as well.
Please give me some advise or is there a possiblity to download certain
update manually?
Please give me a hand here.

Thanks in advance,
Tommy