What is the normal range for wireless connection.?

Get a pre n wireless access point or Pre N router and that should increase the range.

Not a lot you can do for the computer itself. Items between your router and your computer cause interference which will distort your connection.

Without additional money involved you could try changing the channel on your router from something different from the default. Often people's wireless all exist on the same channel and this could cause a little chaos. For instructions changing the channels on your wireless settings bust out your router's instruction manual.

An alternative to that is buying a wireless bridge or range extender. These are separate pieces of hardware you can purchase to enhance your signal or provide access in areas of low signal.

We need more information. Use the edit button on your answer. We need the make and model of your router. For instance, I have a 2Wire router distributed by ATT for dsl. It defaults to 40% of the available power for broadcast. If yours is like that you may be able to simply go into the setup and turn it up

And the card(s) your using on your laptop or pc. You maybe able to find that in your device manager under my computers property's for the laptop/pc.

Make sure your running the very latest device driver(s) for the pc/laptop and the very latest version of the software for the router.

Depending on your ant (detachable or not) you can buy an ant that will focus the signal.

The 1st/2nd generation Wifi systems (11a/b/g) have a range of "upto" 300' depending on if your inside/outside, type of frame (metal or not) in the walls, number of walls between your pc and the router etc. You can also buy wireless repeaters etc.

Wifi 11N appears to have a longer range.

My router is about 50 feet.