There is no comparison between the two.
PS 7 is used by professional photographers and graphic artists. They can do
amazing things with PS7. But this is not what you want to start with. Very
long learning curve.
Start with Dell image expert, play with it to see what you can do with
photos. Then you can go to more sophisticated software such as:
Adobe Photoshop Elements 2.0 (a smaller, more limited version of PS 7)
or
Microsoft Digital Image Suite 9.
Both are about $50.00 after the usual mail-in rebate.
Of these two, Elements has a much better manual to teach you what you can do
with this fancy software. Also you can find many books written by pros about
doing a lot of fancy things with it. To publish on the Web, I would also
select it first.
Image Suite has a terrible manual and you will not find any book about using
it. However it is a little bit easier to use, with great on screen help
display as you edit the photos. It is better if you are into printing at
home. Lots of options for printing.
There is something else. Qimage. This is the best for printing and you can
also edit photos with it. You can download a demo from here:
http://www.ddisoftware.com/qimage/
The interface is a little confusing at first. However it has a great manual.
If you don't know very much about editing photos, download the manual from
the above site and read it. It is free.
What I find is that I go from one software to another because one does a
particular thing better, etc.