I don't recomend it as there is too much risk for total data loss. - if you want to speed things up, get another 100GB drive and which is faster or has a larger cache.
To speed up windows load times go into msconfig and remove start up items which aren't needed. Use
www.sysinfo.org to verify which are needed and which aren't.
Frequent defrags and diskclean ups can help a bit too.