Personally, I would not run an old version.You can get Open Office for free, it can read microsoft documents.
Regarding SandBoxIE, basically, it is very simple.When you install the program,an icon appears on your desktop.Double click on it, your default browser, then opens sandboxed.You can add icons for any program you want to run sandboxed.
I have the paid version, its not only worth every penny, its priceless ( imho )
With the paid version, you have the option to force programs to open boxed.
These are my options, first the default box, is set to auto delete on closure. Certain programs are set, so they are forcibly opened sandboxed., ( you can disable this by simply right clicking on the tray icon,and disable 'forced' programs )
Only certain programs are allowed acces to the net, from the box, so even if you downloaded a keylogger, that named itself firefox.exe, because firefox is already running, a second instance downloaded, could not run in the box
You can recover files from the box.You can scan the contents of the box with anti malware programs, including online scanners.
You can set drives to open boxed, so malware from flash drives, cd's etc open sandboxed.
You can have several boxes with different rules, so you could have a box with no web access allowed.
I have boxes set for inexperienced users of my family, that have no recovery options, they are not allowed to take things from the box.
The list is endless.
You will find lots of info at the site posted by Yokenny.
Obviously S.B will not protect an already infected pc. Also once you take a file out of the box, you are exposed.Its important to scan the box, and run any programs boxed before recovering.SB is very good here for programs that require a reboot to run.
Here are a few snapshots