I took database theory a while ago, but it's not like I had any real thoughts about it other than it helped when designing databases better.
and MS SQL isn't that bad, but I haven't used it extensively. But I suspect most of the comments here are due to the usual "MS sucks / Linux r00lz / I get spoonfed by slashdot" mentality around here. So I won't touch that.
And CSS is a good idea. But I hate implementing it on web pages since browsers are so different.