Computer Won't Start Up Help - URGENT!

Hello

I have an old Compaq Presario 4550 (8 or 9 years old I'm guessing) that went blue and indicated a fatal exception (?) error. I turned it off and then restarted only it will not restart. I have a power saver (sleep) mode and the light for that stays on continuously.

I'm guessing it probably doesn't pay to have it looked at and fixed since its so old?

What's the minimum MB, GB and type of processor I will need to do my minimum amount of computer stuff...I mainly run a photo editing program, Works or Word and surf the internet. What are the differences between the penitium processor, the Celeron processor, the Athlon processor, and the Sempron processor?

If the memory files weren't damaged is there a way to recoup all my files from my hard drive and get them onto a new computer? I know NOTHING about computers but have to get this resolved SOON.

I can't afford more than $500 for a package (daughter left for college $$$$$ this year). Any suggestions appreciated.

Thanks for your kind help

Sandy