Can I delete these files?

My User root folder is full of files that look like this:

NTUSER.DAT{058811b7-1cbf-11dc-a505-00016cef983c}.TM.blf

They are all 512kB in size and many date back months. Are they really needed
or can they be tidied up?

Vista doesn't seem to delete them, but then it doesn't seem to tidy up after
itself in common with most other apps today.

My Vista partition image size just grows and grows enormously every day,
which makes image backing very wasteful on DVD disks and/or external HD space.

NigelS