More specifically, Premiere Elements chugs along when it has to index and create thumbnails for the timeline when I am working on piecing together all the clips that go into a 2.5 hour DVD. I have an old school Pentium 4 running at 3Ghz, and 2 gigs of PC-3200 RAM, with 2 gigs being the most the board supports. For free space, I used to make my swap space drive the D drive, since the C drive was only 80 gigs. The D drive was 250 gigs, but there was always about 90 gigs free. I never let it get below 20 gigs of free space simply because I don't want to get stuck burning disc after disc of data in one shot . I am not sure how quickly Premiere would function now since I added those two SATA drive I bought from Phillyman.
On a similar not, my computer can barely run a 1080p video downloaded from the web. I tried it out with a sample clip off some site. Needless to say, it doesn't play smoothly at all.
Premiere elements isn't terribly demanding on a system or the most part; not nearly as bad as Adobe After Effects, which is what I think I will need to achieve some of the effects in that music video.
Anyhow, a new computer will mean Windows 7, which, according to what I have been reading, will be a great OS to use.