If i had to choose, i would pay no attention to Google PageRank as that will change once you redesign the site and add new content. Instead, i would evaluate the quality of citations each site currently has and I would also consider which domain is easier to remember and brand or fits nicer with targeted keywords.
If those are the true PR numbers, then just looking at the PR data alone the PR3 domain would be better.
However, the question is which domain name is more relevant to what you want to do with it? The domain name is very important. For example, if you are looking to sell red shoes then redshoes.com is a much better domain name than shoes.com.
The age of a domain is one factor search engines take into account and the older the domain is, the better. You can calculate the age of domain by using the date of domain name registration and expiration date.You can find Creation and Expiration date of a domain easily by doing a whois search in sites like WhoisXY.com .Sites that are older have more authority with Google and other search engines because they have been around a while, and aren't some fly-by-night website that could he here today and gone tomorrow.
So,I think 2 years old domain with PR1 is better than the 7 months old domain.