Well, RAID 0 generally fails when a drive goes bad, not as a result of the RAID itself going bad, although tinkering with the RAID configuration after it's setup can torpedo it. Since the data in RAID 0 is stored, half on each drive, a failure of either drive results in a loss of all data on both drives. The drive that didn't fail however, can be reused by repartitioning and formatting it, as though it were a new HDD.
Provided you keep decent backups of anything you consider important, there's really no harm in throwing your two 1 TB HDDs into a RAID 0 array. Expect to empty off both drives, however, so if they are cram packed full of things, you may need to find some temporary storage until you get your RAID array finished. A benefit of RAID 0 is that you should end up with the capacity of all included drives, combined. You won't be sacrificing large quantities of disk space or write time for any parity bits.