Disk cleanup taking hours

Hello

I'm using now Workstation 10, after having used several of the previous versions. Host is Win7 x64 and one guest is WinXP x86.

I decided now to make disk cleanup (under Management) for my XP VM. This VM has two connected virtual disks, one 15 GB and one 30 GB. This cleanup is now taking already over 1 hour (it guessed to clean 4.5 GB of old data) to finish. While this is running is it impossible to use any other VM. The host HDD is an old 500 GB 7200 RPM disk.

Could this be changed so that this cleanup runs in the background? And maybe also add a time guess about how much longer it will take?

Thanks

elkor