|mmm agree re' DbBan... not a good idea... as "eveything" on the drive will go - including that hidden/recovery partition...|
And again if any data on the system now that might be nice to preserve... first adress that issue. If current OS works well enuff... then use it to copy all data off the drive to optical -media; and verify those copies are truly accessible on at least one other system.
If current OS doesn't work... then boot with Knoppix or Ubuntu disk and access/copy data that way...
Then set about the rebuild etc. as per above posts?