G2 did not have a demo version.
In case you haven't run across it, here are the G2 requirements:
Generation 2 System Requirements
Minimum System Requirements
Windows® XP*, 2000*, ME, 98 (Local administrator access required)
Intel® Pentium® 300 or equivalent
Dire X™ 8 (or above) compatible video and sound card
3D accelerated video card with 8 MB (or more) RAM (VooDoo 1 and VooDoo 2 video cards are not supported)
64 MB RAM
500 MB hard drive space
4X CD-ROM drive
Optimum System Requirements
Optimum System Requirements
Intel Pentium 600 or equivalent
3D accelerated video card with 16 MB (or more) RAM (VooDoo 1 and VooDoo 2 video cards are not supported)
128 MB RAM
MultiPlayer System Requirements
Intel Pentium 450 or above
LAN: IPX/SPX or TCP/IP protocol
Internet: TCP/IP connection requires an Internet account and 28.8 Kbps (or faster) modem
64 MB RAM
System Requirements InterLink Controller
USB Port
Compatible FM or FM-selectable transmitter (if using the interface)
Included adapter cord for optional interface use is compatible with most JR®, Hitec®, Tower Hobbies® and Futaba® transmitters. Interface use with Airtronics®/Sanwa radios requires adapter cord GPMZ4062, available separately. Interface adapter cords for additional transmitters available.