We are using the MS SQL database to store some of our more complex data.

Now we have the need for a smaller (and cheap) database, but not as small as Access, something that allows multiple tables, queries, multi users, we do not care about stored procedures and views. Size is not a big issue, we are talking about of tens of thousands records, but speed is a requirement. We were thinking about mySQL but we saw that requires a year distribution fee (the database will be distribuited with our applications, but it will be transparent to the user)

So my question is: where can I find information about which databases are available in the market, and how to compare them? So far I tried google, but I get only zero or a gazillion hits.

Many thanks in advance
Marco