Major problems that I can’t figure out.

Help!!
I built a computer for a neighbor (trying to start a new business) and her Juno email causes illegal operations, also her MS Word does the same and she loses all her info (doesn’t microsave work so she gets frustrated with me) and I have reinstalled the programs etc. Also it turns on by itself and all of the wake up events are disabled. Her system is a 700MHz Duron, with 128 MB ram, 20GB HD, CD-rom, cd-rw, which I purchased from I-systemsUSA via tigerdirect. I has been a few months and I have worked on this to no avail. It works fine for me. What do I do??? Thanks for the help.