deadhook

Okay, I'm not entirely dumb, just when it comes to this and being someone who has a very tough time pulling the trigger on considerable purchases makes it even worse.

I'm currently on a Toshiba M45-S2653 (Pentium M "with Centrino Technology?", 80GB HD, 512MB RAM) which has been problematic from day 1 and now I'm LOST and CLUELESS in computer-shopping hell. I've done some research but am still having trouble understanding a few important things and how they should affect my specific decision.

The ones I'm looking at have either 1 or 2GB of RAM and either the Core 2-Duo or the Dual Core Intel Processors. This is where I just can't figure out if my needs/usage justify spending more money (unfortunately $$ being an huge consideration now) on the better options, how much better the performance really is for my needs or if I'd even notice/care because it's so minor.

Hopefully any "decent" laptop would be a vast upgrade from this Toshiba so I may not need to get a $1200 laptop if there's a $750 model that's plenty capable, fast and will feel like a great upgrade from the one I've been on for the past 2 years.

WHAT I'M LOOKING FOR:
Reliable, reputable brand, plenty fast, capable of what I'd need it for and easy for a dummy like me to take advantage of. 100GB HD is fine for me so that's not an huge consideration.
I use my laptops constantly just not for really "demanding" applications. 90% of the time I've just got 4 or 5 pages/tabs in Firefox open, usually have Photoshop open but not doing very advance graphics, viewing my photos on my HD and then every now and then will download a torrent or two and may stream a movie/music file.

** QUESTIONS: **
- Anyone know of a site that rates/explains in basic terms how the various Intel and AMD processors stack up and which may be right based on someone's needs?

- ** Is there a noticeable or substantial performance difference between say the Core 2-Duo and the one that's a step down from that (Centrino or Pentium Dual Core?)? Would it be enough to even notice or care muchless spend a bunch more money?

- How do the RAM and Processor combinations change performance? In other words, if I had 2GB RAM and the Dual-Core instead of the Core 2-Duo would that be about as good as 1GB RAM with the better processor? That confuses me. If I did go with the Dual Core rather then the Core 2-Duo, would I see a big difference in performance between 1 and 2 GB RAM?

- ** I've read a bunch of Laptop rating sites/threads and really lean toward HP. In YOUR opinion though, what other brand would YOU consider strongly if you were me and what would you make damn sure to stay away from?

There are a million different HP Laptop models it seems but does the model or series itself matter as long as it's got what I need? Any to avoid?

SORRY FOR ALL THE QUESTIONS AND LONG POST. I'M JUST HAVING TROUBLE PULLING THE TRIGGER AND HOPED FOR A LITTLE HELP WITH THE DECISION. I REALLY VERY MUCH APPRECIATE THE FEEDBACK.

Thank you again!!!!!!!!!!!!!!