I'm a Mac girl and would never be able to suggest a PC over a Macintosh. But I can say this...
- I love my laptop and the freedom that it gives me, but I also love my desktop for my huge monitor - it's all personal preference. If the only reason you do NOT want a laptop is b/c you don't want to sit in your recliner while doing homework, then why don't you just put the laptop on a desk and use it when you are doing homework?
- I am a PS junkie and work on it all day while at work, and a couple hours each evening for scrapping - so I say go for PS. But if you like PSE and can use it to do everything you want do, then you could save yourself a lotta money by sticking with it instead of buying PS.
- Monitor size is another personal preference. I LOVE my ginormous monitor that I have at work - it's a dream. Again - personal preference, but I say go with 1. what you have room for, and 2. what you can afford. I would much rather have a nice sized monitor and some extra RAM rather than not enough RAM and a huge monitor. KWIM?
- As far as money... I learned my lesson a long time ago that you get what you pay for. You said you've been through 3 laptops in 5 years - have they broken? too slow? you just wanted a new one? If you are shopping for a $400 laptop right now, I think I would stick with the one you've got a little while longer and keep saving some $$ to upgrade to something a lot "better" - not something with the same specs that's just newer - ya know?
I purchased my Mac Titanium G4 Notebook nearly SEVEN years ago and it's still going like a tank. It's never had so much as a hiccup - never. At the time it really sucked b/c I paid a pretty penny for it, but several of my friends have been through 4 or 5 computers since I bought mine.
Sorry I can't help with PC specifics (brand, model, etc). I'm a mac girl and will never go back.
Good luck with shopping!!