Having a second internal drive ("data drive") is a big plus. You can put all you short-term images, your LR Catalog folder, and your LR Camera Raw cache on there, all of which take up space on your system drive making it work less efficiently, and then you can also move your Windows paging files and such there. I'm not sure of how Lightroom uses "temporary" drive space outside of the Windows page files -- Photoshop has settings that you can use to assign scratch disk locations and space but I haven't seen that in Lightroom.
A couple other things that come to mind: The LR/Camera Raw cache by default is set to a pretty small file size. It's advised to increase that size to say 20 GB. What I'm not sure of is how to do that directly in Lightroom -- I've done this through Photoshop Camera Raw Preferences. Maybe someone "in the know" can speak up.
One other setting to play with is the LR preview size and how long you keep it in the system. Rendering 1:1 previews will help speed up opening images in the Development module, but it can be a slow process -- you can either do this at Import or on the fly for a given shoot. Also, you can keep 1:1 for specified times. The longer you keep them the more cache space gets filled up, so you decide at what point you likely won't need quick access to older files. These settings are available in the Lightroom Catalog Preferences in Edit/Catalog Settings.
