I have 3 options for you.
1)spend 100 dollars on a mod chip and installation, and then spend 100 on a burner.
2)hold out till dual layer (DVD-9) burners become cheap (i think they are 250 right now) and a mod chip. I believe this will have more compatibility with future games and u can burn full DVD movies with all the extra features!!
3)my system. get an hd loader and buy a 120gb hard drive (hd loader=40-50 dollars)(120gb hard drive=100-120 dollars)
note: you can buy any drive from 40gb and above.. 40 is the minimum and the hd loader won't be able to read over 137GB so it is not valuable to buy over 160GB but u can if you want.
make sure that the HD you buy is compadible.
compadibility website: http://ps2drives.x-pec.com/?v_brand=&v_modelnum=&v_size=&v_rpm=&v_buffersize=&v_fitting=&v_working=&v_version=&v_adaptor=&v_postedby=
hd loader website: www.hdloader.com