VLAN Basics

I have never touched VLANs before, so any form of description into the following would be useful.

I have a client who I am doing a new installation for. Their office will comprise of their own PCs, and then a number of LAN ports located around the office for visitors to make use of. The conditions here are that visitors are not able to connect to the main office network, but both the office LAN and the visitor LAN has access to the printer and a few other shared resources.

The network warrants a decent switch anyway, so I am thinking about getting a VLAN-capable one. However, I need a few questions answered.

1: Will VLANs do what I want to accomplish? Create two LANs which are separate, but whereby one can communicate / be routed to the other for access to the printer on the 'Visitor LAN'. Can a VLAN set-up do this?
2: Would this require 2 IP subnets?
3: How can a Layer 2 and Layer 3 switch change the way this works... if at all? For budget reasons, I am looking at a Layer 2 switch which states it has VLAN-support.
4: Finally, how would I go about connecting workstations to the Internet? Default Gateway pointed at the switch, which is then configured to route to the router??? I have no idea!

I am looking for information specific to VLANs and their suitability here. If VLANs will not do what I want to do (I'd appreciate an explanation as to why not, if that is the case), I will install a hardware firewall between two switches and configure the network in a slightly messier and more complicated way... but a way I can guarantee will work.

Thanks in advance!