Depending on your server type you may have to create a new csr for your ssl cert. For instance, Apache servers can simply reuse the old csr, whereas Microsoft IIS and Java-based servers will have to create a new csr. The good news is that if you have to create a new csr, you normally should have the option of selecting a 'create new csr' switch as opposed to having to literally create a new certificate and recreate the old fields like domain name, organization, city, state, etc.
For more information, go to:
Also check out http://www.ssl.com
for some deals on most major SSL cert and wildcard cert brands. To get multi-year certs, you specify that information and the time of purchase, not during creating the csr. The CA will ultimately override what you put in the csr as the duration. Hope this helps.