Have you tried Google-ing for a database?????
I'm amazed by the lack of research you carried in trying to find "any reasonable relational database". What about trying to Google for "database" - there at the top (a sponsored link, yes) is the "world's best selling databse". And you didn't even know about it? I hope your research methods within your chosen acedemic subject is a tad better!
MS SQL easiest to use?!?! God help us! There are millions of users of FileMaker out there, especially within acedemia - it's a shame you didn't realise this before you took the route of "if it's hard to do it must be powerful" and "if it's MS it's probably OK".
It's not too late for you, though - I'm sure you must have other projects on which you could actually try the best of breed apps rather than the de facto MS offering.