It looks like hte 13.4Gb is a recovery partition. On most Dell machines at start up ther eis an option to press one of the function keys to 'restore' it to the factory condition. This 'system' is kept on that partition. If you delete it you will lose the facility to return to factory condition.
The other two partitions seem to be what you have made and you can investigate/change them etc with any good partitioning program. The internal windows program is a bit limited, but there are some good free ones.
As far as XP goes you can install it on one partition but Win 7 home does not have the XP emulator in it.
as far as 32 / 64 bit goes this only applies to the actual way in which the program is written and should not affect the Hard drive; win 7 does a good job of automatically detecting and using the right 32 or 64 bit software a appropriate.
M