I cannot speak for
50miner.org but, I did mine with
50btc.com a long time ago. I did use the software from
50btc.com when I had first started. It did not alter my browser in any way or add ads. I cannot speak for 50miner.org's software and it does look suspicious so, stick with 50btc.com's software. I hope that is where you were downloading lauraallen.
fyi, 50btc.com got its name from back when the block reward was 50 BTC. Not the present 25. Before that halving. I never had a problem with payouts or their software and the pool was very well suited for my understanding when I first had started to learn. I have not mined with them for years but, I do think they are ok. I think I stopped mining with them because I wanted to try a different payment structure and, for no real reason, I never returned. I do not use the 50miner software anymore because I like all the verbose output from console programs but, when I first started this was just easier to understand. Less of a learning curve and we all can remember the sleepless eagerness to just get mining.
Hope you find that joy soon lauraallen!