This leads me to my question: What light weight laptops are people using for travel?
Sounds like memory issue as you said. As to laptops I am a Mac user primarily so there is no option that is small as I would really like, and have travelled with many models [used a G3 iBook for photos for not a speed demon but it was fine and the machine was ALOT slower than anything out now from Apple]
I put my laptops in a backpack or briefcase and it is usually not a real pain - the weight difference beween them is rather negligable between them in the grand scheme of things, partly because Apple does not currently have a real light portable - the current models range from the 13.3" MacBook (5.2 lbs) to the 17" MacBook Pro (6.8 lbs). I curse everything (weight and size) of everything I bring when going to and from plane and to and from hotel or wherever, but once settled the bit of headache (I travel with the 17" now) is worth it, at least for me. ( I find that packing the cables, extra hard drives, power supplies usually become more problematic for me as compared to the laptop itself it terms of size and weight. Also have a 15" Dell laptop, but that never comes along on a trip. I have PCs (laptops/towers) but overall I just prefer Macs, the OS and the way they work.)
That being said, I am also looking at maybe picking up a demo/refurb MacBook - it should be okay to do what I want and I am trying to ween myself from spending too much time attached to the computer when I am diving/on vacation, and when I am in front of a 17" screen I can lost easily as compared to working on a smaller screen
I use the laptops basically for emails and to review things, do quick reviews of material/edits/corrections, make backups etc., but then when I get home do the finishing touches as needed.
Not sure if you are near an Apple store, but you may want to take a look, ask them if you can load some of your photos and play with iPhoto and CS3 (when they start adding it to the machines). Note you can also install Windows on the new Macs either natively or via emulation.
As an aside, you may be able to crossgrade to the Mac versions of CS3, if you decide to look at Macs. Adobe used to let people cross over like that, do not know if they still do.
You should see if you get your machine running (no need to spend extra money if you do not have to, sounds like it something that has an answer) but if you are going to look at another machine, you may want to check out the Macs.