Unable to update vista please help!

I have had this problem for quite some time now, whenever i go to install new
updates they all say they install fine then it tells me to restart. i do so
and when my computer restarts it tells me that updates failed to install.
this happens to allmost every update and all give me the same error code
800703F8. thee is no info anywhere about this error code and i have searched
all over the web. new updates are just piling up and i cant install them.
this is really starting to annoy me and would love some help. i have been
given some technical mumbo jumbo about the problm but i really need an answer
in normal terms =P

Thanks!