Switch Capability Question

Hi,

I am doing a network rejig at home and have a few newbie questions.

Background

I moved my Vodafone cable modem and router to the basement from attic as summer heat has been killing them.The Vodafone Netcomm NF5 felt like it was going to catch on fire so I have swapped back to my old TP Link WR1043ND.

A result is i have used a 20M ethernet cable to reach lounge and connect to Xbox 360.However rather than run an additional two cables for other devices- I am considering the following switch.

http://www.pbtech.co.nz/index.php?z=p&p=SWHTPL1007&name=TP-LINK-TL-SG1005D-5-PORT-GIG-SWITCH-101001000Mbps

My Questions are:

1. Was I right to ditch the Vodafone supplier Netcomm Nf5 for TP Link

2. Will the switch allow multiple devices to connect concurrently ( or is it one device at a time).

3. My chimney creates a wifi shadow so may need to extend the signal coverage via extender or AP.

Do you have any thoughts regarding the following products or alternatives?

http://www.pbtech.co.nz/index.php?z=p&p=NETTPL0850&name=TP-LINK-TL-WA850RE-N300-Wireless-Range-Extender-wi or

http://www.pbtech.co.nz/index.php?z=p&p=NETTPL0830&name=TP-Link-300Mbps-Wireless-N-Range-Extender-Atheros- or

access point

http://www.pbtech.co.nz/index.php?z=p&p=NETTPL0801&name=TP-LINK-TL-WA801ND-300Mbps-Wireless-N-Access-Point

Cheers