Here's a few silly questions, because I think I know the answer to most of them...
1. I have a 2611 router I just bought to play with so I can eventually go for CCNA. It has two interfaces, e0/0 & e0/1. Now, these are ethernet, not fast ethernet (AFAIK). So does that mean they're limited to 10Mb/s, not 100? And how can I check their speed? I tried "show int" and I see nothing in the output about actual speeds...
2. IF they are, in fact only 10Mb/s... I'll be setting up VLAN's in my house which will obviously require routing between them. It's a 100Mb/s network (2924 switches, Cat 5e cabling), but if the router ports are 10Mb/s, and I have to route between VLAN's, will my entire network thus slow down to 10Mb/s?
If the traffic must pass between the VLAN then you will be limited by the router. If it stays layer 2 it will not leave the switch so it will be at 100.
Even if your ports were 100 (ie you had a 2621) you would still not be able to get anywhere near 100m. A 2621 router cannot route traffic that fast. I forget but I think it is in the 20m range max. This is why people use layer3 switches. They tend to be faster than routers if all you require is simple lan to lan routing.
Both the ethernet ports on the 2611 are 10 base T only and do not support 100Mbps speed. There are no modules for the 2600 series router that provide a Fast Ethernet port. The 2620 and 2621 routers come with 1 and 2 Fast Ethernet ports respectively, but these ports are built in on the chassis.
If you connect it to a switch then the speed would be 10Mb/s only.