Generally you should be able to copy the entire install disc onto a external HD (place the disc contents in a folder on the drive). Then open the folder and run the install.
Same thing can be done with a USB flash drive if you have one with enough space.
Alternately you can buy a external USB DVD burner drive, just plug in when you need it. Should be able to find those now days for $50-$60.
Food for thought, there are freebee "office" like software available, I use Open Office 3.3 (helpful for opening those stupid "docx" files, not sure if Office 2003 supports that file type but Office 2007 and up does, and EVERYONE sends me those blasted files)..
