The DVD Will have all software available but if you do a selective installation and remove many of the packages you don't use, you should get OpenSuse10.x to use up about 2GB max. It will fit on that machine but does the machine even have a DVD-Rom drive? Do you have a DvD Burner?

Go for the CD install instead.
Base CDs (choose one)
CD-KDE (695 MB)
or
CD-GNOME (665 MB)
Plus
Add-On CD (optional)
Non-Open Source Software (476 MB)