Novatell mifi 2200 is slow and it stops, my computers can't even open web sights when they're connected to it,

Did you go to the Sprint website? There's info you might find on hooking it up. http://support.sprint.com/support/device/Novatel_Wireless/MiFitrade_2200_by_Novatel_Wireless-novatel_2200

There is a small hole just above the battery cover; this is the reset. Place a pin inside and press down to reset device.

Typically the carriers require you to sign in on the mifi home page to setup your mifi. Once you have gone through the setup you will then setup a typical wireless connection using the SSID and Password either setup or given to you by AT&T. Does the home page have a sign in or setup area? If so that is where I would start.

Open a webpage (i.e. Internet Explorer) and the Three homepage will load. Click on 'My Account' or 'My Three' and then 'DATA Allowance'.
Please click the 'Thanks' button if this helped.

You can reset the modem,router,use latest browsers,you can use torrent for Downloading and Uploading.These helps to increase internet speed...To check your internet uploading and downloading speed visit the site Scanmyspeed.com

Scan it with antivirus

Go to https://www.del.com/support and download the driver you need directly from their site. This should resolve your issue(s).

Mine did this, I went to Best Buy where I bought it. They didn't really seem to know, said it could be the power cord to the wall, but they didn't sell them. But they could set me up with an upgrade (and new 2 year contract that I didn't want). Anyway, I went to Radio Shack and showed them my MiFi 2200 and they had the new wall charger power cord there. Works now, problem solved for $25 instead of a new 2 year contract.

how to unlock a verizon mifi2200

You cannot connect a router to your Mifi as it does not LAn port. You can use wireless access point to amplify your wireless signal