I had the same connectivity issues.  I have 2- hardwired gateway desktops, a HP Laptop, a Compaq laptop (2 months new) both laptops are wireless.  I just bought the wireless n ultra range plus for the HP laptop.  Originally i installed LELA.  Had all the same problems, read the posts, uninstlled LELA, had the same connectivity problems again.  Friday I  reinstalled the router, didn't install LELA. Everything is hooked up, no problems yet.  We'll see if I have problems months from now, hope not. My modem is a little warm too. I found a .5 in stand to set the modem to get a little more air underneath where the vent hole are located.   

Forgot to mention: I don't think I am going to reinstall LELA until I hear some positive feedback on the program.

Later that night: still having connection problems, not as bad as before, but still shows page can't display screen until i repair connection to get new ip address.  Read BTB's fix, going to try it in the morning.  Sounds like its working for others, hope it works for me.

you can find the WPA-PSK TKIP on the router's set up page..

just do this following steps..

open internet explorer and type in on the address bar -- 192.168.1.1

then go to the WIRELESS tab then hit wireless security..

now make sure that the security mode is also in WPA and not WPA2 because you can find two of it..

check the encryption type if its TKIP, then depends on the router..

most often times they have different words such as Passphrase or WPA Key Shared..

but they are just the same..

if it has a character encrypted on it then just copy it..

if it doesnt, then you can type in characters minimum of 8, numbers or letters or both, and its case sensitive.. 

You may be stepping on IP addresses. Check that all your machines don't have a duplicate IP address. On a windows PC go to CMD prompt and type " ipconfig/all "

Look to be sure no two devices have the same IP addres.

SOmetimes the router gets confused and hands out the same ip address to two machines - then you have this problem.

To release the address try the following from the CMD prompt: "ipconfig /release" and then "ipconfig/renew" 

Good luck.