I'mma assume you mean bands from the UK and not just English language music.
There's old school popular rock like The Beatles, The Kinks, The Jam, David Bowie, The Smiths, The Cure. Then there's Britpop from the 90s with bands like Pulp, Oasis, Blur, and Suede. Radiohead, Placebo and Muse have all been significant through the 00s.
If you like metal you might like punk rock, Sex Pistols, The Clash, Buzzcocks, The Stranglers.
Siouxsie & the Banshees have a really good female vocalist.
I'm not familiar with Within Temptation, but I hear them categorized with Epica and After Forever a lot, in case you haven't heard of them.