PC video editing expert? Step this way please!

Hi guys,

I need some tech advice. Here's my scenario;
A few months ago I decided to invest in some prosumer DV equipment. During my spending spree I picked up the following software;

Adobe Premiere Pro,
Adobe After Effects 5.5 Standard,
Adobe Encore,
Adobe Audition,

Unfortunately my current PC (specs at end) has had two years of use prior to installing Premiere Pro and recently some of Microsoft's patches have caused some registry problems that are causing applications to play up. I can't seem to repair it. So far it has not effected Premiere Pro (other than Pro does not see a recent internal DVD burner I added a couple of days ago, but that may not be XP's fault), but overall I am unhappy with the stability of XP right now.

Consequently I'm thinking of doing a complete reformat of my hard drive and creating an 'ideal' environment for Pro since it will be used extensively in the future. I am thinking of partitioning the disk and putting XP on both partitions (not sure if that will create problems in itself, not a lot on the web about it). On one version/side I'll put all my everyday applications. On the other I will put Premiere Pro and the other Adobe products listed above.

Another option is to buy a smallish secondary hard drive and put only XP and my Adobe products on that and boot from it at start up? My main drive would hold all my other stuff. The big advantage (I'm hoping) of this set up will be that I can swap the secondary HD into a new PC when I upgrade in the future. Since my DV footage is kept on my current external HD, hopefully I can carry on flawlessly on the new PC by transferring the secondary drive into it.

However I'm guessing there are load of pitfalls via either of the above routes.
Please point them out and offer your advice?

Thanks for your time.

Regards,
Nigel.
My cuurent PC spec;
P4 2.25Ghz (intel 850 chipset)
1280Mb RDRAM (Rambus)
120Gb internal HD 7200rpm
200Gb external HD 7200rpm USB2/firewire
Geforce 4 Nvidea Ti 4600 128Mb graphics card
Pioneer DVR-107 DVD burner
standard firewire/DV capture card
SoundBlaster Live!(cheapie) sound card

PS I'm happy to try a 'good' registry cleaner/repairer first if anyone can recommend one.