DHCP slowed down by Spanning Tree on switch.

I've found that my DHCP performance (time to hand out leases) is by ways
better(5 sev vs a minute) when I disable "Spanning Trees" on my switches.

My understanding about Spanning Trees was that they are required to provide
optimum paths through a LAN and prevent packets from looping endlessly in
certain topologies. But I've also seen other reccomendations about
disabling Spanning Trees entirely.

What is the deciding factor? If the option exists it must be up to some
good; but then why does it slow me down so much? Perhaps I'm just
misconfiguring my switches! Any advice?

--
Rahul