I just installed Windows Small Business Server 2003 Edition on my computer
which has a 2.8 GHz Intel Pentium 4 processor with 512 mb ram and a
250 GB hard drive. I installed it and when I got into Windows I set up
my network by completing the installation. However when I tried to
login the next time it gave me this error message. It says "The
Current time on the computer and the current time on the network are
different. For more information about Date/Time properties see help
and support." Can you help me with this problem?

Hi, 

this probably has to do with Kerberos (security).
Kerberos tickets by default expire after 5 minutes. That's why you are
getting this error message. Either the time on your domain controller
or the time on your computer is incorrect (probably both, forgive me
my silly joke).
Type:

NET TIME \\servername /SET /Y 
(!! replace servername with the name of the domain controller you're
trying to login to)

to synchronise the computer's clock with that of the domain (controller).
I hope this helps