I'm thinking of buying an adapter to play my old game cartridges through my laptop. I also have a bunch of games on Steam. With a HDMI and a controller, it will make quite a nice little setup. What's the best controller for PC?

http://www.gamesas.com/topic/1466573-the-community-tech-thread-no-129/page-2#entry22862793

Looks like an opinion has been offered in the Tech Thread. More might be coming in there.

I have a third party Saitek Cyborg controller. I love it, but it's been discontinued. If you can find a cheap eBay version I'd personally say it's worth it. I found mine as an open item for USD $15.

Depends on the game really.

A Wired 360 controller will give you the best results with Games for Windows titles (most of them are optimized for that controller)

An after market controller can work, but you will have to be familiar with Xpadder.

I use a PS3 controller. I find that the d-pad on the 360 controller doesn't work well for older games.

I find that the PS3 controller is miles better than the 360 controller if you wish to use a D Pad. I hate the 360 controller's d pad. It's way too jiggly and stuff.

With regards to Xbox 360 pads, do I need a dedicated one for Windows or will my existing ones for my Xbox 360 work already?

The one you have will work, if it's wired. If wireless, you need to buy a wireless receiver.

I still need to pick one up myself at some point, but I think I'm going to wait for the Xbox One controller. It seems really nice.

Have one of those SmartJoy adapters from LikSang before they were shutdown

That would be best for retro gaming, but I don't want two controllers. I want a controller that I can use for new games, such as Left 4 Dead, as well as older titles like the original Sonic.