Page & Administration not working - Java Issue? - Joomla! Forum - community, help and support

good morning all,

i hope can me, i've found similar troubles here nothing has helped. going use "fpa-en.php" script, wouldn't let me upload site because "file unsupported format". i'm using joomla version 1.5.18, , bout month ago javascript apears have broken?

once logged in joomla administrator site, none of buttons on top "site, menu, content, components, extensions, tools, help" work. show text, no indication clickable.

once article manager (those icon buttons clickable on main page, have use arrows main menu again) there no formatting controls above edit window. font, color, add/edit photo, whole grouping not there. preview, save, apply, close & buttons don't work, can't update html , save anyway.

also odd, on main site - http://www.bellatumedspa.com, of multi-level navigation menus appear long list down middle of page, , there's 4 white squares in top left corner.

i "error on page" icon in bottom left of status bar of internet explorer states: "user agent: mozilla/4.0 (compatible; msie 8.0; windows nt 5.1; trident/4.0; ie0006_ver1;en_us; .net clr 2.0.50727; .net clr 3.0.04506.30; .net clr 3.0.4506.2152; .net clr 3.5.30729; .net clr 1.1.4322)
timestamp: mon, 3 dec 2012 04:43:02 utc

message: object expected
line: 87
char: 1
code: 0
uri: http://www.bellatumedspa.com/"

if pull source page, i'm not sure what's wrong:
85 window.onload = function()
86 {
87 var mylist=$("mainmenu");
88 var listitems= mylist.getelementsbytagname("li");
89 var newcount = 0;
90 (i=0; i<listitems.length; i++)
91 {
92 if(listitems[i].classname.search('parent')!=-1)
93 {
94 listitems[i].innerhtml = listitems[i].innerhtml + "<img src='http://www.bellatumedspa.com/templates/pat/images/arrows.gif'>";

this same thing menu occurs in firefox, , on android. don't think anything's been changed recently, i'm @ loss what's wrong. i'm little afraid update more recent version of joomla since backup manager doesn't start because of same issue. otherwise, think wouldn't effect site - it's informational.

one more thing, inherited webmaster duties here else, wasn't 1 set up, please ask other details might need point in right direction?

thanks much,

phil d