I'm trying to get a basic home recording setup going where I can record riff ideas over programmed drums and synths... I have Acid Pro 8 and Fruity Loops but I'm not sure if either is able to record guitars??? Any help or advice on other programs would be very much appreciated
If I'm not mistaken, Fruity Loops can accept midi inputs. If you somehow converted the guitar input to a midi that might work... Fruity Loops isn't a "recording" software though. It's a sequencing program that allows you to export the product. From there you can insert it into a recording application.
Portugal. The Man »–
Try to get Sonar Home Studio, as Acid's stability sucks and Fruity Loops isn't what you want for above reasons.
My Gear:

Ibanez RG 7 EXFX (27'' scale, 2x EMG 707)

Mesa/Boogie Studio .20 Caliber

Line 6 Studio POD GX
I have Acid pro 4 and Fruity Loops. In order to record live guitar tracks you need a preamp that directly imputs into the computer. Your guitar plugs into the preamp and some come with distortion settings/ digital effects so essentially you don't need to bother with your actual amplifier. However you can do that if you want. I recommend a Line6 Toneport because it's simple and delivers a good tone. I use fruity loops only to sequence drum tracks for the music I record in Acid.