MS Word acting up

[laz]

I've noticed that after I have word open for a few hours (working on a lab, paper etc) that NHC says my CPU is at about 85° and when I look in the task manager, word is using anywhere from 20-40 percent of the cpu. After this goes on for a bit, if I save word will lock up and I have to end the process. With a couple excel sheets open at the same time excel doesn't do anything of the sort.

Anyone know what might be going on?