Hi nkyoung and welcome to cdfreaks.
Yup, to both qusestions. Platinum rocks...the best software of it's kind...IMO.
As far as burning to a SL disc, it's simply a matter of choosing dvd5 (SL) as opposed to dvd9 (DL)...bottom of the opening page of platinum. This is the "target" size
To rip the files to the hdd (platinum does this anyway...to a temporry directory) just choose a location on the hdd instead of your burner (ie., target). This is at the top of the opening platinum page.
Similarly, you can choose a "source" other than a dvd. Simply choose the appropriate folder as "source"
Sorry, gotta run...if you need more help, just post back...someone is usually around.
Hope this helps...