The difference of the 2 hub is the speed. For internet sharing, 100M hub will not do any better than the 10M hub since the internection is limited by ISP which is not more than 3M.
If you are using ADSL like Sympatico, you can get 2 or 3 free IPs from ISP, then a hub is enough, but if you use Rogers cable modem, an extra IP address will cost you $10. You may want a router to share the internet. A rouger needs only one IP and forword the traffic to each individual destination on the LAN by NAT. You can also config one computer with 2 NICs on the LAN act as a router or a gateway if you do not want to buy a router.