i've used x64 on my PC and on the ferrari ... it's stable and less buggy than x32, as it was released ...
the only issue is, that some hardware-producers don't offer adapted drivers ...
the partitions are formatet with FAT32 - you can convert them to NTFS ...
for further information type convert /? at the command-prompt or use the forum-search
you can burn the full factory default image with acers eRecovery ...
you also can start the disk-to-disk recovery with acers eRecovery if you didn't delete the hidden recovery-partition ...
acer does not include an OEM-disk ... but there are recovery-disks included to setup the notebooks software in original state ...
but you also can copy a ms OEM-XP-disk and install a clean copy of windows with the oem-key ...