Wireless Network Adapter : which one to Buy????

[suyash_123]

Hi all,
I was seaching for BT3.0, I didnot got it, so i finally went to buy Wireless Network Adapter USb Version. and want help from you guys....

Budget is less than 1400/-

some options to me are
Linksys RangePlus Wireless Network USB Adapter (WUSB100) :- 1690/-
(IEEE 802.11b, IEEE 802.11g,Up to 128-Bit Encryption,Power, Link/Act led lights,2 Internal Antennas )

Belkin N150 Enhanced Wireless USB Network Adapter (F6D4050ak) :- 1455/-
(IEEE 802.11b/g ,150Mbps (in 40MHz mode) ,2.4 GHz ,WEP (64-/128-bit), WPA-PSK (TKIP), WPA2-PSK (AES),Link/Act Led lights)

Belkin Surf and Share Wireless USB Adapter (F7D2101ak) :- 1345/-
(IEEE 802.11n IEEE 802.11g IEEE 802.11b,Up to 300Mbps, Wi-Fi Protected Setup, WPA/WPA2, 64-bit/128-bit WEP encryption ,)

Linksys WUSB54GC Wireless-G USB Adapter :- 1020/-
(IEEE 802.11b/g, Up to 54Mbps ,64/128-Bit WEP, WPA )

Netger N150 Wireless USB Network Adapter (WNA1100) :-850/-
(IEEE 802.11 b/g/n 2.4 GHz ,150Mbps (in 40MHz mode) )


Friends can you tell me something about the importance of

1.IEEE 802.11 n ( is it beneficial as Internet this days are not more than 21.1Mbps)
2. is 54 Mbps speed enough for me in current scenario?
3. what is WPA/WPA2?????? significance
4. is this more secure "64-bit/128-bit WEP encryption" , how?

please reply soon , waiting ur response badly , because want to buy it soon.

Thanks in advance