Typing text names on photos usng XP.?

My friend has taken a lot of photos of plants and wants me to type the names on the photos. I have the photos as JPEG files which are pretty large e.g. 2.4MB or so each. I have opened them with XP Paint and no problem putting the text on BUT when they get printed out the text is way too small, even though I have made it as big as I can using the text bar. She needs the photos to be of good quality when they are printed, and readable names. They will be printed out 6" X 4". The problem is when they are printed out at that size, the writing is so small it can barely be seen.
Can someone please tell me how to do this?

Dear,,, You Have To Rescale Your Picture
Use Stretch/Skew From Image Menu From Mspaint
You Have To Scale It To Your 6X4 Inch If You Want the Text Real View On The picture

After This Save Your Image As A Copy On Other Place
Type The Name You Want In Transparent Mode ( Select the Bottom Rectangle Under Tools Bar)
Save You Image

;)
hope this help

Paint really is a lousy image edit program.
But if it's all you have...

When you draw your text box you may get a text toolbar. If you don't then right click in the text box and select 'Text Toolbar'.
In this toolbar you have the option to select font size.

It would be trial and error but you may want to start at font size 100 and work your way up. (this box lists fonts to size 72 but you can type nearly any number in it that you wish)

DOnt know what imaging programs you have, but an idea would be to copy them into Word, then right button each pic in turn, down to caption and type in the caption you want for each one. Or, copy into Publisher, and create a text frame under each one to type in the caption. YOu could then save them as a jpeg again.