The last I read, all support for Windows XP ends in 2014.
Yes, IE 5.0 will work on Windows Xp. You might want to upgrade to IE 7.0 or 6.0.
Windows XP SP2 can update to SP3 through Windows Update, CD/DVD/USB or downloading the file manually from Microsoft's Websites. Be warned XP support ends as of April 2014.
Windows XP SP3
No
Office 2003 will run on Windows XP.
Windows xp will support 127 usb ports
IE 6.0
The Support!
All versions of Windows XP support multiple users.
No it says that windows XP dosen't support Battlefield 3.
There is extremely limited support for Windows 2000 on HP's website for the HP Pavilion dv6700. Drivers for Windows XP are available.