Sal,

I've always had good luck with genuine Volvo pads. They come with new isolating shims. They are dusty and wear a bit faster than some after market pads, but stop well and don't squeal if properly installed and bedded in. I've also have very good, no squeal results with PBR ceramic pads. I clean the rotor and calipre throughly with brake cleaner, spray some Loctite brake quiet on the backside of the pads and bed them in following the pads instructions. Usually a half dozen of so gradual stops from 40 to near zero without fulling stopping. Allowing a 1/4 mile or so between stops to aviod over heating. I replace the brake hardware every other set. I've never had any noise problems with any of the new Volvo or PBR pads. FCP Groton sells both, here's a link to that site to give you an idea of selection and cost.
http://www.fcpgroton.com/volvo240brake.htm