Can someone point me in the direction of a decent software package for editing the digital phots that I'm taking? I'm looking for something that will enable me to convert to black and white, change the contrast etc. I don't need anything too advanced, and looking for something really cheap, so it doesn't need to be very new. As long as it's easy to use and works on XP then I'm happy. Any suggestions?
Irfanview is free and has a function built in to reduce red-eye in photos but to my knowledge, replacing one colour with another (yellow to red) is quite sophisitcated so you may not get that in the bog-standard programs.
Black to white is less difficult for obvious reasons.
The only prog I've used to change contrast and replace colours is Adobe Photoshop and it's anything but cheap. I had to stay in one whole weekend just to afford it.
Serif is a great software company. They make older versions of many of their programs available as completely free downloads. (I can't imagine Bill Gates ever following that idea!). The program you need is called PhotoPlus. Version 6 will do everything you want. It can be downloaded, along with some other great software, here: http://www.freeserifsoftware.com/
I use 3 programs, all free and do everything you've asked and much more. The free software is so advanced nowadays that there is no point to go to the expense of Photoshop etc unless you want the very advanced modes such as layers or the colour changes as stevie21 has said.
FastStone Image Viewer is the best in my opinion followed closely by IrfanView and Picasa 2. All incredibly easy to use.