computer freezes during incremental backup

I am trying the trial version of the Acronis True Image Home 2010 as a backup.
I am not able to do anything while the incremental backup occurs. If I try to do anything, my computer freezes and I keep having to restart it. I thought maybe it's that maybe it's not compatible with "Windows Live Messenger" which is usually running during the backups. Do you know if there is a problem of compatibility between the two programs? Also, shouldn't I be able to read my emails during the incremental backup?