On Photography, Scrapbooking and Why I am Running out of Computer Space

After driving my daughter to school in the snow this morning I took some photos for the online photography class I am taking -- it was also a useful exercise to calm down from hanging out with a sullen, yet snarky, thirteen year old on her way to school. (If you are interested the course is The Art of Composition with Tracey Clarke and Big Picture Classes -- see the link in the right sidebar). I've been experimenting with shallow depth of field using my new Nikkor 50 mm 1.8 mm lens. Above is one of my favorites. I also tried to get some photos of Chloe. Black dogs really stand out in the snow. She's not very cooperative though -- and is always moving and when I get down on her level to photograph her she comes over to me and I miss the shot.

Actually what I really need is computer advice. I am getting to the point where I have a lot of photos and a lot of digital scrapbooking supplies, and pages in progress on my hard drive and it is pretty much maxed out. I'm doing more with my photography too so those files are much larger than they used to be -- now that I have a DSLR.

So, when is it time to get a new computer? 

I've been using my Dell inspiron 1525 for almost exactly four years now and I am just about out of space on the hard drive.  My husband thinks I should just get an external hard drive and move all of my photos and digital scrapbooking supplies over to it. I've got two issues with this:

1.) I'd have to carry the external hard drive around with the laptop anywhere I wanted to work on photo editing or scrapbook pages and that seems like a pain to me.
2.) I am not sure how reliable external hard drives are -- it would definitely have to be backed up at least to my Mozy online account. And how would that work -- it would have to be connected to the laptop for it to auto backup as it does now. My last external just stopped working with no notice at all.

Of course what I'd really like is a MacBook Pro and a 27 inch monitor to use with it at my desk for photo editing and scrapbooking. Sure, dream on Beth -- that would cost us about $3000. I know because I've checked -- over and over and over again. I can't get the number to go any lower. I could forget about the big screen and just get the laptop and save $999 but that's still not much better.

Or I could just get a new PC with more memory and give up my whole Mac/Apple dream. I must say my Dell has served me really well and continues to do so except for the little space issue.

I'd love some advice from fellow photographers and digital scrapbookers. How do you handle this?

Also I need some of you to tell me why I should pay all that extra money for a Mac vs. a PC. 

Thanks All!