Hi GuardianAngel470
As SuperMedbh says Mass Effect 2 does not supported Controllers, but you can use the xbox 360 controller just go to this link on this forum http://social.bioware.com/forum/Mass-Effect/Mass-Effect-2-PC-Technical-Support-Spoilers-Warning/Mod-Gamepad-360-beta-works-need-help-for-vibrations-1375781-1.html
I use this and it works great the only problem is on the Powerwheel and WeaponWheel the icons are not visible as in the 360 version, but it plays like the 360.

I played mass effect 1 on the xbox 360 and I got mass effect 2 on the pc and I was the same as you I wanted to use my 360 controller, I used Xpadder but I did not like it but I find this mod and it works.

So just download the xbox 360 controller driver at
http://www.microsoft.com/hardware/download/download.aspx?category=Gaming&type=Gaming
Install this driver and plug in you usb 360 pad and you pc will recognise your pad.
Go to this link At the top of this post and download Second
Coalesced_MaxFuel=1500_and_MaxProbes=60 .rar
Copy this file to the mass effect 2 folder in programs files on your local Disk.
Go to Program Files\ Mass Effect 2\BioGame\Config\PC\Cooked\
This file will replace a file called Coalesced.
If you do this right it will work like xbox 360 ,but the rumble will not work.

I hope this helps
All the best UK21smilie