[Commander Zane]

I hope this would be the right place since I want to do gameplay recordings, but I'm looking for a recording program that doesn't chew up too much resources (If possible), and that doesn't have annoying watermarks or splash screens on the corner if it's a Shareware product.

[JGZinv]

Old versions of debut video capture work well in MP4 mode. The new one is quite annoying and useless.

[deathfun]

I've always used FRAPs. It's an excellent program for recording gameplay footage (the FPS counter can be removed) though, not free (if you want all the goodies that is)
Not that that has stopped anyone

[achtung]

FRAPS is pretty much top of the line.

[BloodEagle]

Unless you use hardware based recording.

[Dark RevenantX]

A quad or hex core and a SSD or decent RAID array pretty much records anything on FRAPS with no slowdown at all.