.....I'm based in the UK and looking to trade equities, forex and options. To reiterate, I'm a beginner and from some of the reading I've been doing it looks like a couple of key criteria should probably be education features and demo account.
On the subject of education: depending on who and where you are (and also your learning style) it might help you to attend some live events where you would be able to both get something out of the presentations and meet other people too.
If you're based around London you're spoiled for choice with Manchester and B'ham following on.
As examples, you have brokers such as CMC markets, ActivTrades and Fineco Bank who put on regular events - obviously the basic ones are aimed at getting you to sign up and trade but it doesn't mean that they're useless.
They often get outside well-known traders and educators to come in and deliver seminars on strategies - a recent instance would be Tom Hougaard* (TraderTom) who is presenting at the Traders show at the Novotel in Hammersmith at the end of the month and was also one of Fineco's guest speakers a few weeks ago.
* Tom's strategy seems to be doing reeeally badly atm