[iLinx]

Well your running Windows 7 with 1024mb of ram and a single core cpu, thats where my reasoning came from.
to my experience the new versions of windows office are always laggy until they get patched, i guess reinstalling it, playing around with compatibility, process priority, etc might fix it, or you could just downgrade all together
I have 2007 and it runs fine even on a legacy pc (1.6ghz / 768 mb ram)

Sorry but i dont know much more than that on the topic ^-^