New
#41
You can, but you'll need to do some extra work and use a third party tool to handle the booting, as the newer OS is already on the system.
I'm also making an assumption that the XP disc is only 32 bit, meaning it will give you absolutely nothing over your current install, so why bother?
It I can make an assumption/observation....it seems like you are just digging yourself into a deeper hole of a convoluted system here without knowing what or why you are jumping in. That usually leads to data loss and/or a non-booting system.
If it was me, I'd do one of two things. I'd leave Windows 7 x86 installed as the only OS, and spend my efforts organizing all the partitions and consolidating them. Or, I'd back up my data by getting an external drive, wipe the whole thing clean and installing one OS, preferably Windows 7 x64, cleanly, with a normal drive/partition structure, and be done with it.