You can pick up a cheap-yet-a-really-good DVD-ROM anywhere these days. It doesn't have to be a DVD-Writable drive. As long as the drive can read DVD-ROM and at an affordable price(which shouldn't be too much of a problem for most you guys). I think you should. Even though the technology was introduced decades ago, in the near future PC games will probably get larger than or equal to MGS2 where developers will have to convert to DVD format.
I'm glad I got my DVD-ROM drive(capture DVD movies, rip PS2 Music files) although I didn't expect to see the MGS2 PC to be on the DVD format.