If your looking to win money from free rolls and then build up your bank roll, i would NOT suggest Full Tilt.
For a few reasons,
1. The Freerolls thats Fulltilt hosts are ridiculous, paying the top 27 out of a 2700 tournament, thats 1% that cash. and you really dont make over a dollar unless your on the final table.
2. They dont have true micro cash games, they go as low as .05/.10; which if u win a few cents every 10th free roll then it will take a while. (I wish they had .01/.02)
However, If you get into enough private free rolls, or make 500K play money you can make some decent free roll money. the 500K free roll is probably the best bet as it pays 50% of the tournament (top 18 out of 35ish usually). The minimum is usually 2 Dollars as well.
So Good Luck, I have heard poker stars
is good to start up from nothing, but I havent really tried it much yet.