You must be drawing some serious power if your 25W resistors are exploding and not blowing the fuse. Is it possible you could have shorted the resistors across the battery (bypassing the fuse)? In any case, you should mount your fuse as close as possible to your power source.
I built an h-bridge once for an inverted pendulum project once. I blew a couple mosfets and they shorted, causing shoot-through and nearly catching my breadboard on fire. I added a current sensing shutdown circuit after that. I've got a bunch of pics and stuff here:**broken link removed**