DVd Plextor 712A

I have 1 problem:
I use a blank dvd and i whany to rw a image but the
program: Nero 6.3 it's tell me i don't have enough
space.he same problem even when i try with Dvd
Decrypter.it like this :
Free Space 2,297,888 bytes.PLeae help me.

PLEXTOR DVDR PX-712A 1.05 (ATA)
Current Profile: DVD-R

Disc Information:
Status: Empty
Erasable: No
Free Sectors: 2,297,888
Free Space: 4,706,074,624 bytes
Free Time: 510:40:38 (MM:SS:FF)
Supported Write Speeds: 2x, 4x
Pre-recorded Information:
Manufacturer ID: PRINCO

Physical Format Information (Last Recorded):
Book Type: DVD-R
Part Version: 5
Disc Size: 120mm
Maximum Read Rate: 10.08Mbps
Number of Layers: 1
Track Path: Parallel Track Path (PTP)
Linear Density: 0.267 um/bit
Track Density: 0.74 um/track
First Physical Sector of Data Area: 196,608
Last Physical Sector of Data Area: 2,495,103
Last Physical Sector in Layer 0: 0