There's a pretty good metal scene in Brissle I reckon, lots of metal pubs and nights for what we Bristolians used to call "Jitters" -
www.[b]metal[/b]travelguide.com/europe/england/south-west/[b]bristol[/b]/
Check out my drummer mate's band Mind For Murder, I think they're pretty heavy - https://www.facebook.com/MFMUK - they're playing at Brisfest in September if you're in this neck of the woods already - www.brisfest.co.uk
Another guitarist mate's band Metalhead are worth a look too - https://www.facebook.com/metalheadcovers?ref=ts, the bassist is pretty hot too (no it's not me!)
Re school - http://www.bimm.co.uk/bristol/
Venues wise, The Hatchet, The Croft as Mr F mentioned and The Gryphon too, the Full Moon on Stokes Croft used to be a metal pub, not sure now though sorry. Bristol's pretty lucky music wise, lots of bands including heavier ones play here, check out The Fleece, O2 Academy, The Croft, Louisianna, Bierkeller etc etc.
Rock on!
[size=8]\m/[/size]