Unless your brakes are really worn out, showing symptoms other than the ride-related ones you mention, they probably don't need to be replaced. On my 117k mile '95 850 the front strut mounts are both trashed, and that's what's causing rattles, knocks and squeaks. On the right side it's obvious that the shaft of the strut is no longer centered in the mount. Why the PO didn't bother addressing this at the same time he had new balljoints installed beats me. (Well, he probably got sticker-shocked on the repair cost, but still....)

On my car, you can go to any one of the four corners, push up and down, and watch the whole body take forever to settle down. The shocks and struts are in bad, bad, UNSAFE shape. I can also see that the front sway bar bushings are worn out.

So I'm replacing all that stuff. The strut mounts are a little pricey, (~$100 US each side), and Bilstein HD's aren't free, but I'm really looking forward to bolting everything on this weekend. I can post pics if anyone's interested.