Not the fastest, but certainly the best is Yahoo! It is part directory, part search engine. The directory is compiled by humans. Only websites deemed relevant and of good quality are included. The search engine results come from google.com
I don't think any one can be rated over another. A lot depends on what you are looking for. Sometimes I find one thing on one search engine and something else on another. It is best to try one or two to get a better chance of returning what you are looking for.
I agree with the previous answer www.google.com is very good and most of the time returns what I'm looking for. I like www.profusion.com too. It really comes down to which one you find best when looking for your results.
It's not exactly a search engine, but I can't praise www.ask.co.uk highly enough. Whenever I'm stuck, I use that and 99.999999% of the time it finds the answer. It's brilliant!!