IMO, if you are goning to take planetary Avies then the more disk space the better.
I have 40 gig on this laptop, C: and D:. 14 gig is already taken on the C: with applications and other essentials, so that one is pretty useless except for emergencies (6 gig useless

I remember when......:rolleyes). The D: (20gig total) carries the bare minimum (4 gig), but on a good nights run I can ttake 12-15 gig of avies NP. I have on a number of times needed that spare 5 or so gig on the C:. My suggestion, minimum 60 gig, 100 gig much better.
Then Ram, Ram, Ram. 1 gig. I have 512 on this laptop and comparing it to my desktop (1 gig) it works at snails pace (well not quite but a definate difference) when processing with Registax or ImagesPlus. And don't get me started on running Photoshop on here

It'll do it, but go make a cuppa while waiting for some of the more intensive memory operations.
Yep I wish I had a dvd burner. Even zipped you can't fit many avies onto on cd and if you want to keep a nights session together you will have problems.
If you process on a desktop with good ram and has a dvd burner and you had to make one choice, I'd suggest hdd space. If you had two choices then hdd and then RAM.